title: Catecholaminergic responses in vas deferens isolated from rats submitted to acute swimming stress.
abstract: The study was performed to examine the responses to catecholamines in vas deferens isolated from rats submitted to acute swimming-induced stress. It was demonstrated that acute stress induces a significant subsensitivity of rat vas deferens to norepinephrine. This subsensitivity was inhibited when the experiment was carried out in the presence of either cocaine (10-5 M) or timolol (10-5 M). On the other hand, the rat vas deferens sensitivity to methoxamine was significantly increased by acute swimming-induced stress. Thus, despite acute swimming stress inducing a reduction in response to norepinephrine, the alpha1-adrenoceptor-mediated contractile response was increased. Additionally there were increases in neuronal uptake and beta2-adrenoceptor activity that opposes the alpha1-adrenoceptor activity. Integrated, these phenomena are responsible for the rat vas deferens subsensitivity to norepinephrine which may be involved in body homeostasis in stressogenic situations.
authors: Departamento de Farmacologia, Instituto de Biociencias, Universidade Estadual Paulista (UNESP), Botucatu-SP, Brasil.
authors: A B
authors: AB
authors: Chies
authors: O C
authors: OC
authors: Pereira
mesh_terms: D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D003042:Cocaine / Q000494:pharmacology; D008297:Male; D008729:Methoxamine / Q000494:pharmacology; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D009294:Narcotics / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D013312:Stress, Physiological; D013999:Timolol / Q000037:antagonists & inhibitors; D014649:Vas Deferens / Q000187:drug effects*
chemical_list: D000316:Adrenergic alpha-Agonists; D000319:Adrenergic beta-Antagonists; D009294:Narcotics; D013999:Timolol; D008729:Methoxamine; D003042:Cocaine; D009638:Norepinephrine