BIOM30001 Lecture Notes - Lecture 5: Leptin Receptor, Neuropeptide Y, Proopiomelanocortin

• School: University of Melbourne
• Department: Biomedicine
• Course: BIOM30001
• Professor: Terry Mulhern

Document Summary

Peptides that increase food intake = stimulate appetite and increase energy expenditure. Peptides that decrease food intake = suppress appetite and decrease energy expenditure. Satiety signals (cck) released during or after a meal, in response to cho and fats medulla stop eating. Ghrelin released before a meal stimulates appetite. Mechanoreceptors in stomach (stomach stretches) stop eating. Leptin maintains body weight (chronic) = released in levels proportionate to amount of body fat active transport (across blood brain barrier because its a big molecule, cannot di use) hypothalamus. Ghrelin administrating increases body weight in rodents because stimulates gh receptors (ghsr-1a) in hypothalamus: predominantly synthesised in the stomach, plasma levels inversely proportional to bmi, pre-prandial rise and post-prandial decrease meal initiation. Leptin de ciency causes morbid obesity: morbidly obese mice lacked leptin (high appetite, infertile) Alpha-melanocyte stimulating hormone: endogenous agonist 13 amino acid peptide, released in the pvn, inhibits food intake predominantly via mc4r.