AJP - Cell Physiology, Vol 244, Issue 3 270-C275, Copyright © 1983 by American Physiological Society
Cerebral glucose utilization in awake unstressed rats
R. M. Bryan Jr, R. A. Hawkins, A. M. Mans, D. W. Davis and R. B. Page
Regional cerebral glucose utilization (rCMRGlc) was measured in awake
unstressed rats by use of [2-14C]glucose autoradiography. Rats prepared by
chronic catheterization of the jugular and epigastric veins were placed in
specially designed chambers after surgery. The catheters were passed
through the top of the chambers. Seven days after surgery, plasma glucose
was normal (7.5 mM), plasma ketone bodies were low (0.13 mM), and body
weight was maintained. Plasma epinephrine was 31 pg/ml; approximately 3% of
the level for stressed (immobilized) rats. Injections and blood sampling
through the catheters did not produce changes in heart rate, blood
pressure, plasma catecholamines, or blood metabolites. Visual observations
did not reveal any signs that the rats were aware of the [2-14C]glucose
injections and the subsequent blood sampling. The rCMRGlc in stressed rats
was significantly greater than in unstressed rats. This method provides a
model for physiological studies in unstressed unanesthetized rats.
