BSC 1086C Lecture Notes - Lecture 16: Renal Function, Active Transport, Afferent Arterioles
Document Summary
Passive mechanical process driven by hydrostatic pressure. The glomerulus is very efficient filter because. Its filtration membrane is very permeable and it has a large surface area: glomerular blood pressure is higher (e. g plasma proteins) and function to maintain colloid osmotic pressure of the blood. Volume of filtrate formed per minute by the kidneys (120-125 ml/min) Governed by (and directly proportional to: total surface area available for filtration, filtration membrane permeability, nfp. Gfr is tightly controlled by two types of mechanisms. Intrinsic controls (renal autoregulation) act locally within the kidney: extrinsic controls- nervous and endocrine mechanisms that maintain blood pressure, but affect kidney function. Maintains a nearly constant gfr when map is in the range of 80-180 mm hg. Two types of renal autoregulation: myogenic mechanism, tubuloglomerular feedback mechanism, which senses changes in the juxtaglomerular apparatus. Increase bp -> constriction of afferent arterioles: helps maintain normal gfr, protects glomeruli from damaging high bp.
