Cutaneous heat flow durin heating an in AlZigator mississipiensis
نویسنده
چکیده
SMITN, E. NORBERT. Cutaneous heat fZow during heating and cooZing in Alligator mississipiensis. Am. J. Physiol. 230(S): 12054210. 1976. -Direct in vivo measurement of heat flow across the skin of the American alligator (AlZigator mississipiensis) showed increased heat flow during warming. Mean values at 25OC during warming (15-35°C) in air (airspeed 300 cm/s) were 17.9 t 1.2 SE Cal/cm” per h (mean alligator wt 3.27 kg). Cooling heat flow at the same temperature was 13.6 t 0.57 Cal/cm2 per h. Subdermal heat flow was reduced during warming and was not significantly different from cutaneous heat flow during cooling. This indicated that the alligator was able to control its rate of heat exchange with the environment by altering cutaneous perfusion. Atropine, phenoxybenzamine, nitroglycerin, and Xylocaine did not affect cutaneous heat flow or heating and cooling rates. Atropine blocked bradycardia during cooling.
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