Advances in Physiology Education, Vol 268, Issue 6 49-S55, Copyright © 1995 by American Physiological Society
Renal function in the laboratory rat: a student exercise
R. L. Walker and M. E. Olson
Department of Biological Sciences, Faculty of Medicine, University of Calgary, Alberta, Canada.
Because of the increased concern over use of human body fluids in
physiology teaching laboratories, we developed an exercise in renal
function that utilizes laboratory rats. The purpose is to demonstrate the
role of the kidneys in the homeostatic control of extracellular fluid
volume, plasma ionic concentrations, and osmolarity. Three treatment groups
are utilized: a volume-expanded (access to 1 g/100 ml sucrose) group, a
volume-expanded and salt-loaded (access to 0.9 g/100 ml NaCl) group, and a
volume-depleted (water-deprived) group. A normovolemic control group
(access to tap water) is also included. Rats are housed individually in
metabolic cages that allow accurate measurement of fluid intake and urine
output. Blood samples are removed via cardiac puncture. The animals recover
from this procedure and can be reutilized within 2-3 wk. When class data
are pooled, clear trends are seen that demonstrate the volume-, osmo-, and
ionoregulatory abilities of the kidneys.
