Thermal preference behavior following clonidine, norepinephrine, isoproterenol, and ephedrine
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Updated: Oct 20, 2026
Assessment of Vascular Tone Responsiveness using Isolated Mesenteric Arteries with a Focus on Modulation by Perivascular Adipose Tissues
Published on: June 3, 2019
H J Carlisle1, T S Frost, M J Stock
1Department of Psychology, University of California, Santa Barbara 93106, USA. carlisle@condor.psych.ucsb.edu
Abstract:
A thermal gradient (temperature range 7-45 degrees C) was used to assess ambient temperature (Ta) preferences of rats following treatment with clonidine (25 microg/kg), norepinephrine (NE, 250 microg/kg), isoproterenol (ISO, 50 microg/kg), and ephedrine (EPH, 10 mg/kg). Clonidine produced a preference for a temperature (31.5 degrees C) slightly warmer than that preferred after saline (28.3 degrees C), but this resulted in no significant change in posttest colonic temperature (Tc). NE, ISO and EPH produced a preference for a colder region of the gradient (20-22 degrees C) compared to saline (24.5-28.9 degrees C). Posttest Tc was reduced significantly from 37.7-37.9 degrees C after saline to 37.2 degrees C (NE), 37.3 degrees C (ISO), and 36.8 degrees C (EPH). Thus, given the opportunity to select an environmental temperature, the animals selected a Ta that resulted in significantly lower body temperatures after NE, ISO, and EPH. This suggests that paradoxical thermoregulatory effects of these thermogenic adrenergic agonists are due, at least in part, to a preference for a lower body temperature.
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