30 November 2011 Renal Physiology Announcements: Test # 3 Monday Dec 5 th : CV, Respiratory & part of Renal Feedback on Hemorrhage Diagrams: TAs and Schedule Lab This Week: Respiration Case Studies & Spirometry. Save paper: don’t print out lab materials. Bring textbook and calculator to lab.

1QQ 32 for 8:30 1.What evidence indicates that the abrupt increase in ventilation at the onset of exercise is not the result of negative feedback? 2.Why is the negative feedback system more sensitive to changes in PaCO 2 than PaO 2 ? 3.How is it that hyperventilating immediately before diving allows a pearl diver to hold his breath for a longer interval that he would otherwise be able to?

1QQ 32 for 9:30 1.What evidence indicates that the abrupt increase in ventilation at the cessation of exercise is not the result of negative feedback? 2.Why is the negative feedback system more sensitive to changes in PaCO 2 than PaO 2 ? 3.If a normal healthy resting person is breathing ambient air at sea level and suddenly increases minute ventilation from 7 L/ min to 10 L/min, what would happen to their PaCO 2 and PaO 2 ?

Special terms Filtration: movement of fluid from blood into the lumen of the nephron Reabsorption: the movement of specific compounds from the lumen back into the blood (peritubular capillaries) Secretion: the transport of specific compounds from blood into the lumen Excretion: elimination from the body in urine

Kidneys are source of 3 hormones: Renin, EPO, and Vit D. Kidneys are targets of 3 hormones: ADH, Aldosterone, ANH Topics discussed: cortex, medulla, kidney stones, micturition (detrussor, internal and external urethra sphincters and innervation), incidence of bladder infections by gender, urethral sphincters Tubular fluid vs urine Nephron = tubule S 15

Renal artery = One way in. Two ways out of kidney (renal vein or ureter) S 16 Zoom in on next slide

Fig a Renal corpuscle Juxtamedullary and Cortical Nephrons Peritubular Capillaraies and branches called vasa recta S 19

Fig Three stimuli for secretion of renin from JGC 1) 2) 3) UF in BS TF BC

Fig b

Figure Ultrafiltrate of plasma enters Bowman’s space Composition same as plasma except no formed elements and very few proteins and no substances bound to proteins

Fig Starling Forces Regulated Variable that establishes GFR Glomerular Filtration Rate is 180 L/day =120 ml/min AA EA

Fig Regulating GFR Which happens during hemorrhage? What substances can cause this constriction? Which happens during overhydration?

Fig a

Figure Membrane proteins are segregated into apical (luminal) and basolateral membranes. reabsorption secretion metabolism Amino acidglucose