Martinez-Piñero M G, Milanés M V, Alcaraz C, Vargas M L
Department of Physiology and Pharmacology, School of Medicine, University of Murcia, Spain.
Brain Res. 1994 Dec 30;668(1-2):122-8. doi: 10.1016/0006-8993(94)90518-5.
The present study investigates the role of hypothalamic catecholamines in the effects of morphine on hypothalamo-pituitary-adrenocortical (HPA) axis. Acutely administered morphine (30 mg/kg i.p) increased plasma corticosterone and reduced the hypothalamic noradrenaline (NA) content but it did not change either the dopamine (DA) concentration or the ratio DOPAC/DA. After reserpine administration the hypothalamic contents of NA and DA were drastically reduced without changing plasma corticosterone concentrations. The increase in plasma corticosterone induced by morphine was significantly reduced by the pretreatment with reserpine. The alpha 1- and alpha 2-antagonists prazosin and yohimbine, respectively, significantly antagonized the effect of morphine on plasma corticosterone. The beta-antagonist propranolol also significantly attenuated the increase of corticosterone secretion induced by morphine. The results suggest that the action of the opiate on HPA axis activity may be dependent on stimulatory catecholaminergic systems which utilize alpha 1-, alpha 2- and beta-adrenoceptors.
本研究探讨下丘脑儿茶酚胺在吗啡对下丘脑 - 垂体 - 肾上腺皮质（HPA）轴作用中的角色。急性给予吗啡（30毫克/千克腹腔注射）可增加血浆皮质酮水平，并降低下丘脑去甲肾上腺素（NA）含量，但对多巴胺（DA）浓度或DOPAC/DA比值没有影响。给予利血平后，下丘脑NA和DA含量大幅降低，而血浆皮质酮浓度未发生变化。利血平预处理可显著降低吗啡诱导的血浆皮质酮升高。α1和α2拮抗剂哌唑嗪和育亨宾分别显著拮抗吗啡对血浆皮质酮的作用。β拮抗剂普萘洛尔也显著减弱了吗啡诱导的皮质酮分泌增加。结果表明，阿片类药物对HPA轴活性的作用可能依赖于利用α1、α2和β肾上腺素能受体的刺激性儿茶酚胺能系统。
