Vol. 282, Issue 1, R216-R225, January 2002
Ingestive behavior and body temperature during the ovarian
cycle in normotensive and hypertensive rats
Michael E.
Rashotte1,
Allison M.
Ackert1, and
J.
Michael
Overton2
Departments of 1 Psychology and 2 Nutrition, Food,
and Exercise Sciences, Program in Neuroscience, Florida State
University, Tallahassee, Florida 32306-1270
The relationship between ingestive
behavior (eating + drinking) and core body temperature
(Tb) in naturally cycling female rats was compared in a
normotensive strain (Sprague-Dawley; SD) and a hypertensive strain
reputed to have chronically elevated Tb (spontaneously
hypertensive rats; SHR). Tb (by telemetry) and ingestive
behavior (automated recording) were quantified every 30 s.
Ingestive behavior and Tb were related on all days of the ovarian cycle in both strains, but the strength of that relationship was reduced on the day of estrus (E) compared with nonestrous days.
Several strain differences in Tb were found as well. In SHR, dark-phase Tb was elevated on E, whereas SD remained
at the lower nonestrous values. Fluctuations in dark-phase
Tb were correlated with ingestive behavior in both strains
but had greater amplitude in SHR except on E. Short-term fasting or
sucrose availability did not eliminate elevated dark-phase
Tb on E in SHR. We propose that estrus-related changes
unique to SHR may indicate heightened thermal reactivity to hormonal
changes, ingestive behavior, and general locomotor activity.
spontaneously hypertensive rat; Sprague-Dawley rat; estrus; telemetry; feeding; drinking; fasting; sucrose
