Effect on Body Temperature of Morphine and Ergotamine Injected Into the Cerebral Ventricles of Cats

Morphine and ergotamine have been examined in cats to find out how they affect body temperature when acting on the hypothalamus.The two substances were chosen to investigate whether a substance such as morphine, which reduces the monoamines in the hypothalamus, affects body temperature when injected into the cerebral ventricles, and whether a substance such as ergotamine, which blocks the action of the monoamines in peripheral tissues, exerts this effect also on the anterior hypothalamus.A reduction by morphine of the noradrenaline and adrenaline content of the hypo- thalamus and brain stem has been observed in all species examined, and this effect is prevented by nalorphine (Vogt, 1954; Holzbauer & Vogt, 1954; Gunne, 1959; Maynert & Klingman, 1962; Maynert & Levi, 1965).