Oxytocin antagonism of hypothalamic-induced angina-like ECG changes and pressor effects in the cat

Electrical stimulation of a specific site in the lateral hypothalamus of the cat, in a region posterior to Hess' defense area, results in pressor effects and angina-like ECG changes which consist either of T-wave inversion and ST-segment prolongation or in the appearance of tall T-waves. Oxytocin (10 U, i.v.) administered 15 min prior to stimulation, prevents the former ECG changes and BP rise in 90%, and the latter ECG changes and BP rise in 50% of the animals.