http://www.wellesley.edu/Chemistry/chem227/nucleicfunction/cancer/cancergrowth.gif

The Development of Cancer

http://www.wellesley.edu/Chemistry/chem227/nucleicfunction/cancer/cancer.html

http://www.wellesley.edu/Chemistry/chem227/nucleicfunction/cancer/cancer.html

http://www.medicinenet.com/images/illustrations/butterfly_rash.jpg

The Limbic System

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Cerebral Cortex Thought Limbic System Emotion Thamalus Behavior Hypothalamus Midbrain Pons <--> Cerebellum Basic Body Medulla Functions Spinal Cord Reflexes

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Blood-Brain Barrier

http://psych.unn.ac.uk/users/nick/BBBpp08/img009.jpg

What triggers Na+ channel opening?Mechanical (or physical) stimuli

Eg: heat, pressure, vibration, etc. Called mechanically gated Na+ channelsFound in sensory neurons

Binding of neurotransmitter to a receptorAllows signal to move from neuron to neuronCalled ligand-gated Na+ channelsFound on interneurons and efferent neurons

The opening of these types of sodium channels causes a graded potential, which has variable shape and size depending on the strength of the stimulus.

What triggers Na+ channel opening?(continued)

A change in the membrane potentialIf the sum of the graded potentials caused by mechanical- or ligand-gated channels is sufficient to depolarize the neuron to threshold, then a large number of voltage-gated sodium channels will open, causing an action potential.

The action potential then leads to the release of neurotransmitter, allowing communication between neurons.

Myelin speeds the rate of neurotransmission, and reduces

the energy consumption of neurons

http://www.drugdevelopment-technology.com/projects/rasagiline/rasagiline1.html

Major Neurotransmitters

Small MoleculesNeuropeptides

AcetylcholineNitric OxideBiogenic AminesEpinephrineNorepineprineDopamineSerotoninHistamineAmino AcidsGlutamateAminobutyric Acid (GABA)GlycineAspartateHomocysteineTaurineNucleotidesAdenosineAdenosine triphosphate

Hypothalamic Releasing HormonesCorticotrophic Releasing Hormone

Growth Hormone Releasing HormoneThyrotrophin Releasing Hormone

Pituitary Peptidesß endorphins

OxytoxinVasopressin

Adrenocorticotropic Hormone (ACTH)Thyroid Stimulating Hormone (TSH)

Growth HormoneGastrointestinal Peptides

SecretinSubstance P

InsulinGastrin

NeurotensinSomatostatin

CholecystokininOthers

AngiotensinBradykinin

Neuropeptide YCalcitonin