The thermoregulatory response to noradrenaline in rats tested for stress or pharmacological exposures in the early postnatal period

: Norepinephrine-induced increase of the thermoconductivity of the body surface was depressed in rats exposed to cold, handling or treatment with thyroid hormone or alpha-adrenomimetic (mezatone) during the first week after birth. This effect was enhanced by prolonged cold exposure of adult animals. On the contrary, the norepinephrine-induced increase of heat losses from the tail surface was higher in new-born rats, exposed to cold or treated with beta-adrenomimetic (novodrine) than in control or mezatone-treated groups. The effects of neonatal stress or pharmacological treatment on oxygen consumption and rectal temperature responses to norepinephrine were unsignificant.