1 chapter 18 the endocrine system endocrine and nervous systems work together endocrine and nervous...
TRANSCRIPT
11
Chapter 18Chapter 18The Endocrine SystemThe Endocrine System
Endocrine and nervous systems work Endocrine and nervous systems work togethertogether
Endocrine systemEndocrine system hormones released into the bloodstream hormones released into the bloodstream
travel throughout the bodytravel throughout the body results may take hours, but last longerresults may take hours, but last longer
Nervous systemNervous system certain parts release hormones into bloodcertain parts release hormones into blood rest releases neurotransmitters excite or rest releases neurotransmitters excite or
inhibit nerve, muscle & gland cellsinhibit nerve, muscle & gland cells results in milliseconds, brief duration of results in milliseconds, brief duration of
effectseffects
22
General Functions of General Functions of HormonesHormones
Help regulate:Help regulate: extracellular fluidextracellular fluid metabolismmetabolism biological clockbiological clock contraction of cardiac & contraction of cardiac &
smooth musclesmooth muscle glandular secretionglandular secretion some immune functionssome immune functions
Growth & developmentGrowth & development ReproductionReproduction
33
Endocrine Glands DefinedEndocrine Glands Defined Exocrine glandsExocrine glands
secrete products into ducts which empty into secrete products into ducts which empty into body cavities or body surfacebody cavities or body surface
sweat, oil, mucous, & digestive glandssweat, oil, mucous, & digestive glands Endocrine glandsEndocrine glands
secrete products (hormones) into bloodstreamsecrete products (hormones) into bloodstream pituitary, thyroid, parathyroid, adrenal, pinealpituitary, thyroid, parathyroid, adrenal, pineal other organs secrete hormones as a 2nd other organs secrete hormones as a 2nd
functionfunction hypothalamus, thymus, pancreas,ovaries,testes, hypothalamus, thymus, pancreas,ovaries,testes,
kidneys, stomach, liver, small intestine, skin, heart kidneys, stomach, liver, small intestine, skin, heart & placenta& placenta
44
Hormone ReceptorsHormone Receptors
Hormones only affect target cells with specific Hormones only affect target cells with specific membrane proteins called receptorsmembrane proteins called receptors
55
Role of Hormone Role of Hormone ReceptorsReceptors
Constantly being synthesized & broken Constantly being synthesized & broken downdown
A range of 2000-100,000 receptors / A range of 2000-100,000 receptors / target celltarget cell
Down-regulationDown-regulation excess hormone, produces a decrease in excess hormone, produces a decrease in
number of receptorsnumber of receptors receptors undergo endocytosis and are degradedreceptors undergo endocytosis and are degraded
decreases sensitivity of target cell to hormonedecreases sensitivity of target cell to hormone Up-regulationUp-regulation
deficiency of hormone, produces an increase deficiency of hormone, produces an increase in the number of receptorsin the number of receptors
target tissue more sensitive to the hormonetarget tissue more sensitive to the hormone
66
Blocking Hormone Blocking Hormone ReceptorsReceptors
Synthetic hormones that block Synthetic hormones that block receptors for naturally occurring receptors for naturally occurring hormoneshormones RU486 (mifepristone) binds to the RU486 (mifepristone) binds to the
receptors for progesterone preventing it receptors for progesterone preventing it from maintaining the uterus in a pregnant from maintaining the uterus in a pregnant womanwoman
used to induce abortionused to induce abortion brings on menstrual cyclebrings on menstrual cycle
Hormone is prevented from interacting Hormone is prevented from interacting with its receptors and can not perform with its receptors and can not perform its normal functionsits normal functions
77
Circulating & Local HormonesCirculating & Local Hormones
Circulating hormonesCirculating hormones act on distant targetsact on distant targets travel in bloodtravel in blood
Local hormonesLocal hormones paracrines act on paracrines act on
neighboring cellsneighboring cells autocrines act on autocrines act on
same cell that same cell that secreted themsecreted them
88
Lipid-soluble HormonesLipid-soluble Hormones SteroidsSteroids
lipids derived from lipids derived from cholesterol on SERcholesterol on SER
different functional different functional groups attached to groups attached to core of structure core of structure provide uniquenessprovide uniqueness
Thyroid hormonesThyroid hormones tyrosine ring plus tyrosine ring plus
attached iodines are attached iodines are lipid-solublelipid-soluble
Nitric oxide is gasNitric oxide is gas
99
Water-soluble HormonesWater-soluble Hormones Amine, peptide and Amine, peptide and
protein hormonesprotein hormones modified amino modified amino
acids or amino acids acids or amino acids put togetherput together
serotonin, serotonin, melatonin, melatonin, histamine, histamine, epinephrineepinephrine
some glycoproteinssome glycoproteins EicosanoidsEicosanoids
prostaglandins prostaglandins
1010
Hormone Transport in Hormone Transport in BloodBlood
Protein hormones circulate in free Protein hormones circulate in free form in bloodform in blood
Steroid (lipid) & thyroid hormones Steroid (lipid) & thyroid hormones must attach to transport proteins must attach to transport proteins synthesized by liversynthesized by liver
1111
General Mechanisms of Hormone General Mechanisms of Hormone ActionAction
Hormone binds to cell surface or receptor Hormone binds to cell surface or receptor inside target cellinside target cell
Cell may thenCell may then synthesize new moleculessynthesize new molecules change permeability of membranechange permeability of membrane alter rates of reactionsalter rates of reactions
Each target cell responds to hormone Each target cell responds to hormone differentlydifferently liver cells---insulin stimulates glycogen synthesisliver cells---insulin stimulates glycogen synthesis adipose---insulin stimulates triglyceride synthesisadipose---insulin stimulates triglyceride synthesis
1212
Action of Lipid-Soluble Action of Lipid-Soluble HormonesHormones
Hormone diffuses Hormone diffuses through phospholipid through phospholipid bilayer & into cell bilayer & into cell
Binds to receptor Binds to receptor turning on/off turning on/off specific genesspecific genes
New mRNA is formed New mRNA is formed & directs synthesis & directs synthesis of new proteinsof new proteins
New protein alters New protein alters cell’s activitycell’s activity
1313
Action of Water-Soluble Action of Water-Soluble HormonesHormones
Can not diffuse Can not diffuse through plasma through plasma membranemembrane
Hormone receptors Hormone receptors are integral are integral membrane proteins membrane proteins act as first messengeract as first messenger
1414
Amplification of Hormone Amplification of Hormone EffectsEffects
Single molecule of hormone binds to Single molecule of hormone binds to receptorreceptor
One molecule of epinephrine may One molecule of epinephrine may result in breakdown of millions of result in breakdown of millions of glycogen molecules into glucose glycogen molecules into glucose moleculesmolecules
1515
Hormonal InteractionsHormonal Interactions Permissive effectPermissive effect
a second hormone, strengthens the effects of the a second hormone, strengthens the effects of the firstfirst
thyroid strengthens epinephrine’s effect upon thyroid strengthens epinephrine’s effect upon lipolysislipolysis
Synergistic effectSynergistic effect two hormones acting together for greater effecttwo hormones acting together for greater effect estrogen & LH are both needed for oocyte estrogen & LH are both needed for oocyte
productionproduction Antagonistic effectsAntagonistic effects
two hormones with opposite effectstwo hormones with opposite effects insulin promotes glycogen formation & glucagon insulin promotes glycogen formation & glucagon
stimulates glycogen breakdownstimulates glycogen breakdown
1616
Control of Hormone Control of Hormone SecretionSecretion
Regulated by signals from nervous Regulated by signals from nervous system, chemical changes in the blood system, chemical changes in the blood or by other hormonesor by other hormones
Negative feedback control (most Negative feedback control (most common)common) decrease/increase in blood level is decrease/increase in blood level is
reversedreversed Positive feedback controlPositive feedback control
the change produced by the hormone the change produced by the hormone causes more hormone to be releasedcauses more hormone to be released
Disorders involve either hyposecretion Disorders involve either hyposecretion or hypersecretion of a hormoneor hypersecretion of a hormone
1717
Negative Feedback SystemsNegative Feedback Systems
Decrease in blood Decrease in blood levelslevels
Receptors in Receptors in hypothalamus & hypothalamus & thyroidthyroid
Cells activated to Cells activated to secrete more TSH secrete more TSH or more T3 & T4or more T3 & T4
Blood levels Blood levels increaseincrease
1818
Positive FeedbackPositive Feedback
Oxytocin stimulates Oxytocin stimulates uterine contractionsuterine contractions
Uterine contractions Uterine contractions stimulate oxytocin stimulate oxytocin releaserelease
1919
Hypothalamus and Pituitary Hypothalamus and Pituitary GlandGland
Both are master endocrine glands since their Both are master endocrine glands since their hormones control other endocrine glandshormones control other endocrine glands
Hypothalamus is a section of brain above Hypothalamus is a section of brain above where pituitary gland is suspended from stalkwhere pituitary gland is suspended from stalk
Hypothalamus receives input from cortex, Hypothalamus receives input from cortex, thalamus, limbic system & internal organsthalamus, limbic system & internal organs
Hypothalamus controls pituitary gland with 9 Hypothalamus controls pituitary gland with 9 different releasing & inhibiting hormonesdifferent releasing & inhibiting hormones
2020
Pea-shaped, 1/2 inch gland found in Pea-shaped, 1/2 inch gland found in sella turcica of sphenoidsella turcica of sphenoid
Anterior lobe = 75% Anterior lobe = 75% Posterior lobe = 25%Posterior lobe = 25% ends of axons of 10,000 neurons found in ends of axons of 10,000 neurons found in
hypothalamushypothalamus
Anatomy of Pituitary GlandAnatomy of Pituitary Gland
2121
Flow of Blood to Anterior Flow of Blood to Anterior PituitaryPituitary
Controlling hormones enter bloodControlling hormones enter blood Travel through portal veinsTravel through portal veins Enter anterior pituitary at capillariesEnter anterior pituitary at capillaries
2222
Human Growth HormoneHuman Growth Hormone Produced by somatotrophsProduced by somatotrophs Within target cells increases synthesis of Within target cells increases synthesis of
insulinlike growth factors that act locally insulinlike growth factors that act locally or enter bloodstreamor enter bloodstream common target cells are liver, skeletal common target cells are liver, skeletal
muscle, cartilage and bonemuscle, cartilage and bone increases cell growth & cell division by increases cell growth & cell division by
increasing their uptake of amino acids & increasing their uptake of amino acids & synthesis of proteinssynthesis of proteins
stimulate lipolysis in adipose so fatty acids stimulate lipolysis in adipose so fatty acids used for ATPused for ATP
retard use of glucose for ATP production so retard use of glucose for ATP production so blood glucose levels remain high enough to blood glucose levels remain high enough to supply brainsupply brain
2323
Regulation of hGHRegulation of hGH Low blood sugar Low blood sugar
stimulates release of stimulates release of GNRH from GNRH from hypothalamushypothalamus anterior pituitary releases anterior pituitary releases
more hGH, more glycogen more hGH, more glycogen broken down into glucose broken down into glucose by liver cellsby liver cells
High blood sugar High blood sugar stimulates release of stimulates release of GHIH from GHIH from hypothalamushypothalamus less hGH from anterior less hGH from anterior
pituitary, glycogen does pituitary, glycogen does not breakdown into not breakdown into glucoseglucose
2424
Diabetogenic Effect of Diabetogenic Effect of Human Growth HormoneHuman Growth Hormone
Excess of growth hormoneExcess of growth hormone raises blood glucose concentrationraises blood glucose concentration pancreas releases insulin continuallypancreas releases insulin continually beta-cell burnoutbeta-cell burnout
Diabetogenic effectDiabetogenic effect causes diabetes mellitis if no insulin causes diabetes mellitis if no insulin
activity can occur eventuallyactivity can occur eventually
2525
Thyroid Stimulating Hormone Thyroid Stimulating Hormone (TSH)(TSH)
Hypothalamus regulates thyrotroph Hypothalamus regulates thyrotroph cellscells
Thyrotroph cells produce TSHThyrotroph cells produce TSH TSH stimulates the synthesis & TSH stimulates the synthesis &
secretion of T3 and T4secretion of T3 and T4 Metabolic rate stimulatedMetabolic rate stimulated
2626
Follicle Stimulating Hormone Follicle Stimulating Hormone (FSH)(FSH)
Releasing hormone from Releasing hormone from hypothalamus controls hypothalamus controls gonadotrophsgonadotrophs
Gonadotrophs release Gonadotrophs release follicle stimulating hormone follicle stimulating hormone
FSH functions FSH functions initiates the formation of follicles within the initiates the formation of follicles within the
ovaryovary stimulates follicle cells to secrete estrogenstimulates follicle cells to secrete estrogen stimulates sperm production in testesstimulates sperm production in testes
2727
Luteinizing Hormone (LH)Luteinizing Hormone (LH)
Releasing hormones from hypothalamus Releasing hormones from hypothalamus stimulate gonadotrophsstimulate gonadotrophs
Gonadotrophs produce LHGonadotrophs produce LH In females, LH stimulatesIn females, LH stimulates
secretion of estrogensecretion of estrogen ovulation of 2nd oocyte from ovaryovulation of 2nd oocyte from ovary formation of corpus luteumformation of corpus luteum secretion of progesteronesecretion of progesterone
In males, stimulates interstitial cells In males, stimulates interstitial cells to secrete testosterone to secrete testosterone
2828
Prolactin (PRL)Prolactin (PRL) Hypothalamus regulates Hypothalamus regulates
lactotroph cellslactotroph cells Lactotrophs produce prolactinLactotrophs produce prolactin Under right conditions, prolactin Under right conditions, prolactin
causes milk production causes milk production Suckling reduces levels of Suckling reduces levels of
hypothalamic inhibition and hypothalamic inhibition and prolactin levels rise along with prolactin levels rise along with milk productionmilk production
Nursing ceases & milk production Nursing ceases & milk production slowsslows
2929
Adrenocorticotrophic Adrenocorticotrophic HormoneHormone
Hypothalamus Hypothalamus releasing hormones releasing hormones stimulate corticotrophsstimulate corticotrophs
Corticotrophs secrete Corticotrophs secrete ACTH & MSHACTH & MSH
ACTH stimulates cells ACTH stimulates cells of the adrenal cortex of the adrenal cortex that produce that produce glucocorticoidsglucocorticoids
3030
Melanocyte-Stimulating Melanocyte-Stimulating HormoneHormone
Secreted by corticotroph cellsSecreted by corticotroph cells Releasing hormone from Releasing hormone from
hypothalamus increases its release hypothalamus increases its release From the anterior pituitaryFrom the anterior pituitary
Function not certain in humans Function not certain in humans (increase skin pigmentation in frogs )(increase skin pigmentation in frogs )
3131
Posterior Pituitary Gland Posterior Pituitary Gland (Neurohypophysis)(Neurohypophysis)
Does not synthesize Does not synthesize hormoneshormones
Consists of axon Consists of axon terminals of terminals of hypothalamic hypothalamic neurons neurons
Neurons release two Neurons release two neurotransmitters neurotransmitters that enter capillariesthat enter capillaries antidiuretic hormoneantidiuretic hormone oxytocinoxytocin
3232
OxytocinOxytocin Two target tissues both involved in Two target tissues both involved in
neuroendocrine reflexesneuroendocrine reflexes During deliveryDuring delivery
baby’s head stretches cervixbaby’s head stretches cervix hormone release enhances hormone release enhances
uterine muscle contractionuterine muscle contraction baby & placenta are deliveredbaby & placenta are delivered
After deliveryAfter delivery suckling & hearing baby’s cry stimulates milk suckling & hearing baby’s cry stimulates milk
ejectionejection hormone causes muscle contraction & milk ejectionhormone causes muscle contraction & milk ejection
3333
Oxytocin during Oxytocin during Labor Labor
Stimulation of uterus by babyStimulation of uterus by baby Hormone release from Hormone release from
posterior pituitaryposterior pituitary Uterine smooth muscle Uterine smooth muscle
contracts until birth of babycontracts until birth of baby Baby pushed into cervix, Baby pushed into cervix,
increase hormone releaseincrease hormone release More muscle contraction More muscle contraction
occursoccurs When baby is born, positive When baby is born, positive
feedback ceasesfeedback ceases
3434
Antidiuretic Hormone Antidiuretic Hormone (ADH)(ADH)
Known as Known as vasopressinvasopressin
FunctionsFunctions decrease urine decrease urine
productionproduction decrease sweatingdecrease sweating increase BPincrease BP
3535
Regulation Regulation of ADHof ADH
DehydrationDehydration ADH releasedADH released
OverhydrationOverhydration ADH inhibitedADH inhibited
3636
Thyroid GlandThyroid Gland
On each side of trachea is lobe of thyroidOn each side of trachea is lobe of thyroid Weighs 1 oz & has rich blood supplyWeighs 1 oz & has rich blood supply
3737
Photomicrograph of Thyroid Photomicrograph of Thyroid GlandGland
3838
Actions of Thyroid Actions of Thyroid HormonesHormones
T3 & T4 = thyroid T3 & T4 = thyroid hormones responsible for hormones responsible for our metabolic rate, our metabolic rate, synthesis of protein, synthesis of protein, breakdown of fats, use of breakdown of fats, use of glucose for ATP glucose for ATP productionproduction
Calcitonin = responsible Calcitonin = responsible for building of bone & for building of bone & stops reabsorption of stops reabsorption of bone (lower blood levels bone (lower blood levels of Calcium)of Calcium)
3939
Control of T3 & Control of T3 & T4 SecretionT4 Secretion
Negative feedback Negative feedback systemsystem
Low blood levels of Low blood levels of hormones stimulate hormones stimulate hypothalamushypothalamus
It stimulates It stimulates pituitary to release pituitary to release TSHTSH
TSH stimulates gland TSH stimulates gland to raise blood levelsto raise blood levels
4040
Parathyroid GlandsParathyroid Glands
4 pea-sized glands found on back of thyroid 4 pea-sized glands found on back of thyroid glandgland
4141
Parathyroid HormoneParathyroid Hormone
Raise blood calcium levelsRaise blood calcium levels increase activity of osteoclastsincrease activity of osteoclasts increases reabsorption of Ca+2 by kidneyincreases reabsorption of Ca+2 by kidney promote formation of calcitriol (vitamin promote formation of calcitriol (vitamin
D3) by kidney which increases absorption D3) by kidney which increases absorption of Ca+2 and Mg+2 by intestinal tractof Ca+2 and Mg+2 by intestinal tract
Opposite function of calcitoninOpposite function of calcitonin
4242
Regulation of Calcium Blood Regulation of Calcium Blood LevelsLevels
High or low blood levels of Ca+2 stimulate the High or low blood levels of Ca+2 stimulate the release of different hormones --- PTH or CTrelease of different hormones --- PTH or CT
4343
Adrenal GlandsAdrenal Glands
One on top of each kidneyOne on top of each kidney 3 x 3 x 1 cm in size and weighs 5 grams3 x 3 x 1 cm in size and weighs 5 grams Cortex produces 3 different types of hormones Cortex produces 3 different types of hormones
from 3 zones of cortexfrom 3 zones of cortex Medulla produces epinephrine & norepinephrineMedulla produces epinephrine & norepinephrine
4444
Structure of Adrenal GlandStructure of Adrenal Gland
Cortex derived from mesodermCortex derived from mesoderm Medulla derived from ectodermMedulla derived from ectoderm
4545
Regulation of AldosteroneRegulation of Aldosterone
4646
GlucocorticoidsGlucocorticoids 95% of hormonal activity is due to 95% of hormonal activity is due to
cortisolcortisol Functions = help regulate metabolism Functions = help regulate metabolism
increase rate of protein catabolism & increase rate of protein catabolism & lipolysislipolysis
conversion of amino acids to glucoseconversion of amino acids to glucose stimulate lipolysisstimulate lipolysis provide resistance to stress by making provide resistance to stress by making
nutrients available for ATP productionnutrients available for ATP production raise BP by vasoconstrictionraise BP by vasoconstriction anti-inflammatory effects reduced (skin anti-inflammatory effects reduced (skin
cream)cream) reduce release of histamine from mast cellsreduce release of histamine from mast cells decrease capillary permeabilitydecrease capillary permeability depress phagocytosisdepress phagocytosis
4747
Regulation of Regulation of GlucocorticoiGlucocorticoi
dsds Negative feedbackNegative feedback
4848
Androgens from Zona Androgens from Zona ReticularisReticularis
Small amount of male hormone Small amount of male hormone producedproduced insignificant in malesinsignificant in males may contribute to sex drive in femalesmay contribute to sex drive in females is converted to estrogen in is converted to estrogen in
postmenopausal femalespostmenopausal females
4949
Adrenal MedullaAdrenal Medulla
Chromaffin cells receive direct Chromaffin cells receive direct innervation from sympathetic nervous innervation from sympathetic nervous systemsystem develop from same tissue as postganglionic develop from same tissue as postganglionic
neuronsneurons Produce epinephrine & norepinephrineProduce epinephrine & norepinephrine Hormones are sympathomimeticHormones are sympathomimetic
effects mimic those of sympathetic NSeffects mimic those of sympathetic NS cause fight-flight behaviorcause fight-flight behavior
Acetylcholine increase hormone Acetylcholine increase hormone secretion by adrenal medullasecretion by adrenal medulla
5050
Anatomy of PancreasAnatomy of Pancreas
Organ (5 inches) consists of head, body & tailOrgan (5 inches) consists of head, body & tail Cells (99%) in acini produce digestive enzymesCells (99%) in acini produce digestive enzymes Endocrine cells in pancreatic islets produce hormonesEndocrine cells in pancreatic islets produce hormones
5151
Cell Types in the Pancreatic Cell Types in the Pancreatic IsletsIslets
Alpha cells (20%) produce Alpha cells (20%) produce glucagonglucagon
Beta cells (70%) produce insulinBeta cells (70%) produce insulin Delta cells (5%) produce Delta cells (5%) produce
somatostatinsomatostatin F cells produce pancreatic F cells produce pancreatic
polypeptidepolypeptide
5252
Regulation of Glucagon & Insulin Regulation of Glucagon & Insulin SecretionSecretion
Low blood glucose Low blood glucose stimulates release stimulates release of glucagonof glucagon
High blood glucose High blood glucose stimulates stimulates secretion of insulinsecretion of insulin
5353
Ovaries and TestesOvaries and Testes
OvariesOvaries estrogen, progesterone, relaxin & inhibinestrogen, progesterone, relaxin & inhibin regulate reproductive cycle, maintain regulate reproductive cycle, maintain
pregnancy & prepare mammary glands for pregnancy & prepare mammary glands for lactationlactation
TestesTestes produce testosteroneproduce testosterone regulate sperm production & 2nd sexual regulate sperm production & 2nd sexual
characteristicscharacteristics
5454
Pineal GlandPineal Gland
Small gland attached to 3rd ventricle of brainSmall gland attached to 3rd ventricle of brain Melatonin responsible for setting of biological Melatonin responsible for setting of biological
clockclock Jet lag & SAD treatment is bright lightJet lag & SAD treatment is bright light
5555
Effect of Light on Pineal Effect of Light on Pineal GlandGland
Melatonin secretion producing sleepiness Melatonin secretion producing sleepiness occurs during darkness due to lack of occurs during darkness due to lack of stimulation from sympathetic ganglionstimulation from sympathetic ganglion
5656
Seasonal Affective Disorder and Jet Seasonal Affective Disorder and Jet LagLag
Depression that occurs during winter Depression that occurs during winter months when day length is shortmonths when day length is short
Due to overproduction of melatoninDue to overproduction of melatonin TherapyTherapy
exposure to several hours per day of exposure to several hours per day of artificial light as bright as sunlightartificial light as bright as sunlight
speeds recovery from jet lagspeeds recovery from jet lag
5757
Thymus GlandThymus Gland
Important role in maturation of T cellsImportant role in maturation of T cells Hormones produced by gland promote Hormones produced by gland promote
the proliferation & maturation of T cellsthe proliferation & maturation of T cells thymosinthymosin thymic humoral factorthymic humoral factor thymic factorthymic factor thymopoietinthymopoietin
5858
Miscellaneous Hormones Miscellaneous Hormones EicosanoidsEicosanoids
Local hormones released by all body cellsLocal hormones released by all body cells Leukotrienes influence WBCs & inflammationLeukotrienes influence WBCs & inflammation Prostaglandins alterProstaglandins alter
smooth muscle contraction, glandular secretion, smooth muscle contraction, glandular secretion, blood flow, platelet function, nerve transmission, blood flow, platelet function, nerve transmission, metabolism etc.metabolism etc.
Ibuprofen & other nonsteroidal anti-Ibuprofen & other nonsteroidal anti-inflammatory drugs treat pain, fever & inflammatory drugs treat pain, fever & inflammation by inhibiting prostaglandin inflammation by inhibiting prostaglandin synthesissynthesis
5959
Nonsteroidal Anti-inflammatory Nonsteroidal Anti-inflammatory DrugsDrugs
Answer to how aspirin or ibuprofen works Answer to how aspirin or ibuprofen works was discovered in 1971was discovered in 1971 inhibit a key enzyme in prostaglandin synthesis inhibit a key enzyme in prostaglandin synthesis
without affecting the synthesis of leukotrieneswithout affecting the synthesis of leukotrienes Treat a variety of inflammatory disordersTreat a variety of inflammatory disorders
rheumatoid arthritisrheumatoid arthritis Usefulness of aspirin to treat fever & pain Usefulness of aspirin to treat fever & pain
implies prostaglandins are responsible for implies prostaglandins are responsible for those symptomsthose symptoms
6060
Growth FactorsGrowth Factors Substances with mitogenic qualitiesSubstances with mitogenic qualities
cause cell growth from cell divisioncause cell growth from cell division Many act locally as autocrines or paracrinesMany act locally as autocrines or paracrines Selected list of growth factors (Table 18.12)Selected list of growth factors (Table 18.12)
epidermal growth factorepidermal growth factor platelet-derived growth factorplatelet-derived growth factor fibroblast growth factorfibroblast growth factor nerve growth factornerve growth factor tumor angiogenesis factorstumor angiogenesis factors transforming growth factorstransforming growth factors
6161
Stress & General Adaptation Stress & General Adaptation SyndromeSyndrome
Stress response is set of bodily changes Stress response is set of bodily changes called general adaptation syndrome (GAS)called general adaptation syndrome (GAS)
Any stimulus that produces a stress response Any stimulus that produces a stress response is called a stressoris called a stressor
Stress resets the body to meet an emergencyStress resets the body to meet an emergency eustress is productive stress & helps us prepare eustress is productive stress & helps us prepare
for certain challengesfor certain challenges distress type levels of stress are harmfuldistress type levels of stress are harmful
lower our resistance to infectionlower our resistance to infection
6262
Alarm Reaction (Fight-or-Flight)Alarm Reaction (Fight-or-Flight)
Initiated by hypothalamic stimulation Initiated by hypothalamic stimulation of sympathetic portion of the ANS & of sympathetic portion of the ANS & adrenal medullaadrenal medulla
Dog attackDog attack increases circulationincreases circulation promotes ATP synthesispromotes ATP synthesis nonessential body functions are inhibitednonessential body functions are inhibited
digestive, urinary & reproductivedigestive, urinary & reproductive
6363
Resistance ReactionResistance Reaction Initiated by hypothalamic releasing Initiated by hypothalamic releasing
hormones (long-term reaction to stress)hormones (long-term reaction to stress) corticotropin, growth hormone & thyrotropin corticotropin, growth hormone & thyrotropin
releasing hormonesreleasing hormones ResultsResults
increased secretion of aldosterone acts to increased secretion of aldosterone acts to conserve Na+ (increases blood pressure) and conserve Na+ (increases blood pressure) and eliminate H+eliminate H+
increased secretion of cortisol so protein increased secretion of cortisol so protein catabolism is increased & other sources of catabolism is increased & other sources of glucose are foundglucose are found
increase thyroid hormone to increase increase thyroid hormone to increase metabolismmetabolism
Allow body to continue to fight a stressorAllow body to continue to fight a stressor
6464
ExhaustionExhaustion
Resources of the body have become Resources of the body have become depleteddepleted
Resistance stage can not be maintainedResistance stage can not be maintained Prolonged exposure to resistance reaction Prolonged exposure to resistance reaction
hormoneshormones wasting of musclewasting of muscle suppression of immune systemsuppression of immune system ulceration of the GI tractulceration of the GI tract failure of the pancreatic beta cellsfailure of the pancreatic beta cells
6565
Stress and DiseaseStress and Disease
Stress can lead to disease by inhibiting the Stress can lead to disease by inhibiting the immune systemimmune system hypertension, asthma, migraine, gastritis, hypertension, asthma, migraine, gastritis,
colitis, and depressioncolitis, and depression Interleukin - 1 is secreted by macrophagesInterleukin - 1 is secreted by macrophages
link between stress and immunitylink between stress and immunity stimulates production of immune substancesstimulates production of immune substances feedback control since immune substance feedback control since immune substance
suppress the formation of interleukin-1suppress the formation of interleukin-1
6666
Aging and the Endocrine Aging and the Endocrine SystemSystem
Production of human growth hormone decreasesProduction of human growth hormone decreases muscle atrophymuscle atrophy
Production of TSH increase with age to try and stimulate Production of TSH increase with age to try and stimulate thyroid thyroid decrease in metabolic rate, increase in body fat & decrease in metabolic rate, increase in body fat &
hypothyroidismhypothyroidism Thymus after puberty is replaced with adiposeThymus after puberty is replaced with adipose Adrenal glands produce less cortisol & aldosteroneAdrenal glands produce less cortisol & aldosterone Receptor sensitivity to glucose declinesReceptor sensitivity to glucose declines Ovaries no longer respond to gonadotropinsOvaries no longer respond to gonadotropins
decreased output of estrogen (osteoporosis & atherosclerosis)decreased output of estrogen (osteoporosis & atherosclerosis)
6767
Pituitary Gland DisordersPituitary Gland Disorders
Hyposecretion during childhood = pituitary Hyposecretion during childhood = pituitary dwarfism (proportional, childlike body)dwarfism (proportional, childlike body)
Hypersecretion during childhood = giantismHypersecretion during childhood = giantism very tall, normal proportionsvery tall, normal proportions
Hypersecretion as adult = acromegalyHypersecretion as adult = acromegaly growth of hands, feet, facial features & growth of hands, feet, facial features &
thickening of skinthickening of skin
6868
Thyroid Gland DisordersThyroid Gland Disorders Hyposecretion during infancy Hyposecretion during infancy
results in dwarfism & retardation results in dwarfism & retardation called cretinismcalled cretinism
Hypothyroidism in adult produces Hypothyroidism in adult produces sensitivity to cold, low body temp. sensitivity to cold, low body temp. weight gain & mental dullnessweight gain & mental dullness
Hyperthyroidism (Grave’s disease)Hyperthyroidism (Grave’s disease) weight loss, nervousness, tremor & weight loss, nervousness, tremor &
exophthalmos (edema behind eyes)exophthalmos (edema behind eyes) Goiter = enlarged thyroid (dietary)Goiter = enlarged thyroid (dietary)
6969
Cushing’s SyndromeCushing’s Syndrome
Hypersecretion of glucocorticoidsHypersecretion of glucocorticoids Redistribution of fat, spindly arms & legs due to Redistribution of fat, spindly arms & legs due to
muscle lossmuscle loss Wound healing is poor, bruise easilyWound healing is poor, bruise easily
7070
Addison’s diseaseAddison’s disease
Hypersecretion of glucocorticoidsHypersecretion of glucocorticoids hypoglycemia, muscle weakness, low hypoglycemia, muscle weakness, low
BP, dehydration due to decreased Na+ BP, dehydration due to decreased Na+ in bloodin blood
mimics skin darkening effects of MSHmimics skin darkening effects of MSH potential cardiac arrestpotential cardiac arrest
7171
Diabetes Mellitus & Diabetes Mellitus & HyperinsulinismHyperinsulinism
Diabetes mellitus marked by hyperglycemiaDiabetes mellitus marked by hyperglycemia excessive urine production (polyuria)excessive urine production (polyuria) excessive thirst (polydipsia)excessive thirst (polydipsia) excessive eating (polyphagia)excessive eating (polyphagia)
Type I----deficiency of insulin (under 20)Type I----deficiency of insulin (under 20) Type II---adult onsetType II---adult onset
drug stimulates secretion of insulin by beta cellsdrug stimulates secretion of insulin by beta cells cells may be less sensitive to hormonecells may be less sensitive to hormone