Social stress induced pressure breathing and consequent blood pressure oscillation

A large amplitude blood pressure oscillation occurs during social defeat in a territorial fight between male rats, and during the application of a psychosocial stimulus associated with this defeat. Synchronous recording of blood pressure, intrathoracic pressure and diaphragm activity shows that the blood pressure oscillation coincides with a typical respiratory pattern called 'pressure breathing', during which a strongly positive intrathoracic pressure with expiration can be observed. The expiration was relatively prolonged and accompanied by a rise in blood pressure and a decrease in heart frequency. These alterations outlast the applied social respectively psychosocial stimulations. The results of this study suggest that behaviorally induced pressure breathing is of importance to attentional processes during social stimulation. The contribution to the development of hypertension is discussed.