NR 508 | NR508 Advanced Pathophysiology- Endocrine Study guide.

NR 508 | NR508 Advanced Pathophysiology- Endocrine Study guide. Hormone function - ligands that bind to their respective intra- or extracellular receptors. Hormone secretion -Regulated through a negative feedback system. -When target cell response is achieved, feedback signals the hormone to decrease its output. Water- Soluble Hormones - Catecholamines and Peptides -Free molecules - The only hormones that are circulating free are available for binding with receptors. - Active-form: Free circulating available to exert an effect. --Faster in moving - Plasma 1/2 life correlates directly to the % of protein binding Lipid- Soluble Hormones - Steroids, thyroid hormones - Bound to plasma proteins. Major sites of hormone degradation and excretion liver and kidneys Negative Feedback DECREASE subsequent synthesis DECREASE secretion of hormone Decrease in maximal responsiveness of hormone May be due to: - A decrease in # functional target cells - A decrease in # of receptor cells. - Limited concentration of an enzyme - Increase concentration of noncompetitive inhibitor