Beta-adrenergic antagonist prevents anxiety like behavior and natural killer cells migration to the spleen in a model of cohabitation with sick partners

Abstract

Cohabitation for 11 days with two Ehrlich tumor bearing-mice: two mice from control group were treated with vehicle (experimental day 1) and the other mouse was kept undisturbed (companion of health partner). Between ED6 and ED11, CHP were treated with vehicle or propranolol. Two mice from experimental group were inoculated with Ehrlich tumor cells i.p. and the other was kept undisturbed (companion of sick partner). Between ED6 and ED11, CSP were treated with vehicle or propranolol. During psychological stress, catecholamines produced by the sympathetic nervous system (SNS) regulate the immune system and cohabitation for 11 days with two Ehrlich tumor bearing-mice induces psychological stress. Besides, the aversive effects in cohabitation with sick partners are related with the release of odor cues. After cohabitation with sick companions the open field test was used to measure behaviors characteristic of anxiety and indicated that the cohabitation increase in anxiety-like behavior was blocked by pre-treatment with the beta-adrenergic antagonist propranolol. Pre-treatment with the beta-adrenergic antagonist propranolol did not significantly alter corticosterone levels indicating no difference in activation of the hypothalamic-pituitary-adrenal (HPA) axis. Likewise propranolol pre-treatment abrogated the migration of natural killer (NK) cells to the spleen. Collectively, these data suggest that behavioral and immune changes in the model of cohabitation with sick partners occur through beta-adrenergic dependent signaling.