Thermoregulatory processes

Cook LL, Edens FW, Tilson HA. 1988a. Possible brainstem involvement in the modification of thermoregulatory processes by chlordecone in rats. Neuropharmacology 27(9) 871-879. 

Cook LL, Gordon CJ, Tilson HA, et al. 1987. Chlordecone-induced effects on thermoregulatory processes in the rat. Toxicol Appl Pharmacol 90 126-134. 

Every componnd of this series differs to a certain degree from the other in their qualitative, yet primarily quantitative characteristics. They all act on the CNS by causing moderate sedative and antiemetic effects, affecting thermoregulatory processes, skeletal muscle, endocrine system, and by potentiating action of analgesics. 

The skin receives heat from the core by passive conduction and active skin blood flow (Table 5.3). It transfers this heat to the surroundings by convection, radiation, and evaporative (perspiration and diffusion) mechanisms. All of these mechanisms are unregulated or passive except evaporation from sweating. The sweating process is actively controlled by the humarrs thermoregulatory center where the rate of sweat secretion is proportional to eleva tions in core and skin temperature from respective set point temperatures (Table 5.3). 

Sweating, the other powerful heat loss mechanism actively regulated by the thermoregulatory center, is most developed in humans. With about 2,6 million sweat glands distributed over the skin and neurally controlled, sweat secretion can vary from 0 to 1 I7(h m ). The other, lesser, passive evaporative process of the skin is from the diffusion of water. The primary resistance to this flow is the stratum corneum or outermost 15 pm of the skin. The diffusion resistance of the skin is high in comparison to that of clothing and the boundary layer resistance and as a result makes water loss by diffusion fairly stable at about 500 grams/day. 

First, changes in body temperature must reflect a central process, because body temperature is regulated centrally. To produce hyperthermia, psychotogens must somehow enhance sympathetic drive and/or block cholinergic drive on the thermoregulatory centers of the hypothalamus. 

Ni may mimic or substitute for essential elements (i.e., for Ca in the hypothalamic thermoregulatory center resulting in hypothermia for Mg and Ca in enzyme processes). 

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