Behavioral Temperature Regulation Research Articles

Sensory feedback in regulation of body weight: is there a ponderostat?

IT has been postulated that “some correlate of body weight” might control daily food intake1,2. This could work through sensory feedback, as in the case of behavioural temperature regulation. In thermal sensation a stimulus (limited to between 15° and 45° C) feels pleasant when it is conducive to homoeo-thermia and unpleasant when it threatens homoeothermia. This transformation of pleasantness is dependent not only on internal signals but also on the thermoregulatory set point3. The change of sensation from pleasant to unpleasant depending on the internal state also applies to taste and smell4,5. We have explored this phenomenon further, to determine whether these changes in olfactory and gustatory sensations also were dependent on a set-point related to body weight. If modification of body weight also affects gustatory and olfactory sensation, this will provide strong evidence for (a) the existence of a regulatory process for body weight, and (b) the use of sensory feedback in feeding behaviour.

Behavioral Temperature Regulation in the Bullfrog, Rana catesbeiana

of body temperature during normal diurnal activity was 26--33 C, and the mean was approximately 300 C. The critical thermal maximum was 38.20 C. Body temperatures corresponded more closely to dry than to wet bulb air temperatures. Behavioral thermoregulation is achieved by changes in location and alterations in posture. Radiant energy is used as a heat source, and pond water is used either as a heat source or as a heat sink. Cooling is augmented by postural adjustments which increase the amount of surface area exposed to evaporation. Postural thermoregulation was observed more frequently in young bullfrogs (which often occupy the warmest microenvironments available) than in adults. Temperatures of the surface and shallow waters of small ponds may influence frogs to emerge onto the bank where they are exposed to insolation. While out of water bullfrogs may heat, cool, or maintain a relatively constant body temperature depending on prevailing environmental conditions and related postural adjustments.

Behavioral temperature regulation in the squirrel monkey: changes induced by shifts in hypothalamic temperature.

Behavioral temperature regulation in the squirrel monkey: changes induced by shifts in hypothalamic temperature.

The effect of dimethylsulfoxide on behavioral temperature regulation.

Dimethylsulfoxide (DMSO) has received much attention because of its possible, albeit controverted, therapeutic value. Relatively large doses can be safely given to experimental animals; e.g., the LD50 for ip administration in rats is 13.08 gm/kg . DMSO is an excellent solvent and has proved useful as a vehicle for the parenteral administration of antibiotics and other drugs. Biological actions of DMSO were recently reviewed . DMSO has been widely used as a cryoprotective agent for single cells and tissues . Its effect on cold-exposed intact animals, however, has received little study. Intraperitoneal injection of DMSO (3-6 gm/kg) causes a slight fall in the body temperature of mice and rats maintained at ordinary room temperatures. The same doses can cause deep hypothermia and death within a few hours during exposure to an ambient temperature of 1°C . Oxygen consumption by cold-exposed rats and hamsters is significantly reduced following DMSO treatment , and this implies a reduction in heat production needed for the maintenance of thermal balance under cold stress. Methods. Subjects. The subjects were 58 unshaved, Lung-Evans male rats, weighing an average of 281 (240-340) gm.

22. The effect of dimethyl sulfoxide on behavioral temperature regulation: J. A. Panuska (Department of Biology, Georgetown University, Washington, D.C.)

22. The effect of dimethyl sulfoxide on behavioral temperature regulation: J. A. Panuska (Department of Biology, Georgetown University, Washington, D.C.)

Heat intake and hypothalamic temperature during behavioral temperature regulation.

Heat intake and hypothalamic temperature during behavioral temperature regulation.

Critical temperature for instrumental response acquisition in hypothermic rats

Fifty-one previously untrained adult white rats were cooled to colonic temperature of 18.5 C and were rewarmed to various body temperatures between 23 and 31 C. After their body temperature stabilized at a chosen level, rats were placed in a chamber with the possibility of using a lever-activated heat reinforcement apparatus. The temperature of the chamber was 2 C. Each experiment lasted 180 min. During this time the rats either started to press the lever steadily for external heat or at the end of this experiment they became even more hypothermic. In a group of 41 rats kept at a body temperature of 25 C or above, 38 animals used the simple heat reinforcement apparatus and responded effectively, thus rewarming themselves to euthermia. Animals at a higher body temperature acquired the response earlier than animals whose body temperature was lower. When the body temperature was 25 C or below, the rats failed to acquire the response. Thus it appears that body temperature of 25 C is a critical body temperature for this simple response acquisition. behavioral temperature regulation; body temperature; heat reinforcement; hypothermia; learning; performance Submitted on April 1, 1965