BIOL 2060 Lecture Notes - Lecture 21: Renal Function, Afferent Arterioles, Vasopressin

• School: York University
• Department: Biology
• Course: BIOL 2060
• Professor: Hernan Humana

Document Summary

Release & action: vasopressin released by hypothalamus, vasopressin is only hormone that regulates osmolarity, specialized neurons in hypothalamus responsible for its production & release. These neurons are triggered by two stimuli: sti(cid:373)uli"s: os(cid:373)ore(cid:272)eptors & salt (cid:272)o(cid:374)(cid:272)e(cid:374)tratio(cid:374). Os(cid:373)ore(cid:272)eptors a(cid:272)ti(cid:448)ated, (cid:448)asopressi(cid:374) released: other stimuli are ecf volume. They change together due to capillary absorption & secretion. This triggers receptor in left atria (volume receptors are low pressure type of baroreceptors present on left atria). If lots of fluid in left atria, it inhibits signalling in neurons. Global constriction increases tpr & lowers glomerulus filtration. This activates water channel insertion in membrane to reabsorb as much water. This restores plasma volume and decrease salt concentration- achieve normal osmolarity: vasopressin helps efficiently reabsorb water independent to what happens with salt. One hormone capable of moving water independent to sodium: mutations in vasopressin occurs results in diabetes ine.