BIOLOGY 225 Lecture Notes - Lecture 22: Lipolysis, Ketogenesis, Gluconeogenesis
Document Summary
Connected to the hypothalamus via direct neuronal connection. Neurons that originate in hypothalamus terminate here. Neurohormones oxytocin and vasopressin are synthesized in cell: oxytocin is important for reproduction milk ejection. Body and travel in vesicles down axons. First-order endocrine pathway: hypothalamus receives sensory input, hypothalamus serves as integrating center. Precisely controlled: blood glucose too low brain cannot function, blood glucose too high osmotic balance of blood disturbed. Hormones: insulin lowers blood glucose levels, glucagon raises blood glucose levels. An exocrine and endocrine organ: exocrine secretes bicarbonate and enzymes, endocrine hormones involves with intermediary metabolism (insulin and glucagon) Major hormones of the pancreas: insulin beta (b) cells. Contains an a, b and c chain which are composed of amino acids (total 51 amino acids) Insulin peptide family: insulin, relaxin, insulin-like growth factors: glucagon alpha (a) cells. Increase glucose levels in bloodstream: somatostatin delta (d) cells, others. Amino acids and free fatty acids into cells: anabolic. Is also lipogenic, glyconeogenic: inhibits catabolism.
