PSL201 - Renal.docx

101 views2 pages
21 Apr 2012

For unlimited access to Study Guides, a Grade+ subscription is required.

PSL201 - Renal
Funtions of the Urinary System
- filter blood
- regulate ionic composition of plasma
- regulate osmolarity of plasma
- regulate volume of plasma
- regulate pH of plasma
o this all causes the formation of urine
Anatomy of the Urinary System
- the functional units of the kidneys are the nephrons (bowman’s capsule,
proximal tubule, descending limb on henle, ascending loop of henle, and the
distal tubule
- the DT drains into the collecting duct
- filtration occurs at the renal corpuscle which includes the bowman’s capsule
and glomerulus
o glomerular filtrate is the same as plasma but lacking protein
- reabsorption and secretion occurs within the tubules of the nephron (see
slides for diagrams)
- kidneys receive a large part of cardiac output via the renal artery
Basic Renal Exchange Processes
- glomerular filtration is driven by the four starling forces:
o glomular capillary hydrostatic pressure
o hydrostatic pressure inside the bowman’s capsule
o the osmotic pressure of fluids in BC
o the osmotic pressure in the glomerulus
- normal filtration is 125 mL/min
- the filtered load is the quantity of a certain solute that is filtered at the
- GFR stays constant with 3 intrinsic mechanisms:
o Myogenic regulation of smooth muscle in the afferent arteriole
o Tubuglomular feedback
o Mesangial cell contraction
- Extrinsic mechanisms:
o Sympathetic control of smooth muscle in the afferent and efferent
- When solutes are transported across the tubular epithelium by carrier
proteins during reabsorption or secretion a transport maximum can be
o When all carriers are saturated
o Plasma concentration at which solute appears in urine is the renal
Regional Specialization of Renal Tubules
- proximal tubule is specialized to reabsorb large quantities of solutes and
water, and returns it to the blood
Unlock document

This preview shows half of the first page of the document.
Unlock all 2 pages and 3 million more documents.

Already have an account? Log in

Get access

$10 USD/m
Billed $120 USD annually
Homework Help
Class Notes
Textbook Notes
40 Verified Answers
Study Guides
1 Booster Class