Clonidine-induced body temperature changes in rats with anterior or posterior cortical damage

Behavioral and temperature changes induced by clonidine in the developing rat

Changes in core body temperature and the behavioral activation produced by clonidine were measured in 10-day-old rats at 3 different ambient temperatures (25, 30 and 36 degrees C). Behavioral activation after clonidine is comprised of head raising and rotational movements of the limbs which result in locomotion in open areas and wall climbing if the animal is confronted by a vertical surface. Clonidine enhanced locomotion and wall climbing at all environmental temperatures, but a drug-induced hypothermia was found only in the 25 and 30 degrees C testing conditions. This suggests that the clonidine-induced motor changes are not secondary to a fall in body temperature. In a second experiment the open field responses to clonidine at 25 degrees C were observed in 10-day-old rats pretreated with phentolamine (2 and 15 mg/kg), phenoxybenzamine (2 and 15 mg/kg) or naloxone (0.2 and 2 mg/kg). Phentolamine pretreatment at 15 mg/kg reduced locomotion, wall climbing and attenuated the reduction in core temperature. Phenoxybenzamine at 15 mg/kg only affected the clonidine-induced change in temperature. Thus, it is likely that these behavioral and temperature changes are adrenergically mediated and that the clonidine-induced locomotion and temperature effects may be due to different alpha-adrenergic receptors.

Changes in body temperature after administration of adrenergic and serotonergic agents and related drugs including antidepressants

This survey, the third in a series, presents extensive tabulations of literature, primarily since 1965, on thermoregulatory effects of adrenergic and serotonergic agonists and their antagonists including ergot alkaloids, amphetamines, tryptamines, monoamine oxidase inhibitors, tricyclic and other antidepressants, a variety of other agents which alter presynaptic aminergic mechanisms including reserpine, 6-hydroxydopamine, p-chlorophenylalanine, alpha-methyltyrosines, cocaine, guanethidine and bretylium. The information listed includes the species used, route of administration and dose of drug, the environmental temperature at which the experiments were performed, the number of tests, the direction and magnitude of body temperature change and remarks on the presence of special conditions, such as age or lesions, or on the influence of other drugs, such as antagonists, on the response to the primary drug.