Anti-anaphylactic action in the mouse of thyrotropin-releasing hormone (TRH) is mediated through β1-adrenoceptive effectors

Abstract

Intravenous or intracerebroventricular administration of thyrotropin-releasing hormone (TRH) significantly improved survival in immunized mice subjected to fatal anaphylaxis by intravenous challenge with an antigen. This protective action of TRH was blocked by pretreatment with the β-adrenergic antagonist propranolol (5 mg/kg), or by prior administration of the cardioselective β 1-antagonist, metoprolol (5 mg/kg), but not by pretreatment with the β 2-selective antagonist, butoxamine (5 mg/kg). It is suggested, based on the present and previous findings that the anti-anaphylactic effect of TRH in the mouse is mediated through activation of β 1-adrenoceptive effectors, secondary to central stimulation of sympathomedullary release of catecholamines.