PSL300H1 Lecture Notes - Lecture 6: Pituitary Gland, Skeletal Muscle, Proopiomelanocortin
Document Summary
Secretes catecholamines (fight or flight response- sympathetic ns) Catecholamines: stressor sympathetic nervous system activates, spinal cord signal preganglion sympathetic neuron, adrenal medulla activated release hormones from chromaffin cells, most released: epinephrine, medium: norepinephrine, just a little: dopamine. 1 receptor: decrease activity (vasoconstriction: found on smooth muscle. 2 receptor: increase activity (dilation: found on arteries, brochioles. 1 receptor: increase activity (increase contraction force: found in the heart. ** catecholamines are able to produce a diverse set of effects, because of their selectivity for catecholamine receptors (1), and also their affinity based on blood concentrations (2). Symptoms: rash (urticaria, hypotension- due to systemic vasodilation, tightening of upper airways, gastrointestinal nausea, vomiting, diarrhea. High dose of epinephrine: alpha receptor @ high concentrations vasoconstriction, beta receptor only on bronchioles bronchiole dilation. All steroids, therefore all form from cholesterol (starting material: enzyme expressed in each level = different. Cannot cope w/ stress (sicknesses & sick often)
