Pharmacology Review:
Endocrinology & Vitamins Presented by: A Nelson Avery, MD Board Certified in Toxicology, Preventive Medicine and Internal Medicine Clinical Professor and Director Preventive Medicine Residency Program
[email protected]
Endocrine Agents
A Nelson Avery, MD
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Insulin ► Beta cells à proinsulin à hydrolyzed into C- peptide (which has no function) and insulin à
ê glucose ► Mechanism to release insulin: – In response to glucose and other sugars, certain amino acids (leucine, arginine) & vagus activity à – é Intracellular ATP levels à close ATP- dependent K+ channels à ê outward K+ efflux à – Depolarization of β cell and open voltage gated Ca++ channels à influx of Ca++ à triggers release of insulin A Nelson Avery, MD
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Insulin ► Insulin receptors function as transmembrane tyrosine kinases ► Activates cGMP ► Promotes glucose utilization in skeletal muscle and adipose and ê gluconeogenesis ► Promotes glycogen storage (liver and muscle) ► é Fat synthesis (triglycerides) in liver and fat cells;; ê lipolysis ► é Amino acid uptake and é protein synthesis ► Toxicity: hypoglycemia, lipoatrophy, insulin resistance
A Nelson Avery, MD
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Insulin: Types preparation
onset
duration
peak
0-15 mins