The hypothalamic and neurohypophysial oxytocic activities in stressed rats: independence from beta-adrenergic blockade.

A distinct decrease of oxytocin was found in the hypothalamus of immobilized rats but not of those exposed to cold. Similarly, the content of oxytocin was lower in the neurohypophysis of rats immobilized for 24 hr but, on the contrary, increased in animals exposed to cold for 24 hr. Propranolol did not modify the mentioned changes brought about by immobilization or exposure to cold.