Nock B, Cicero T J
Department of Psychiatry, Washington University School of Medicine, St. Louis, Missouri 63110.
Horm Behav. 1991 Mar;25(1):29-37. doi: 10.1016/0018-506x(91)90037-i.
The opiate agonist morphine caused a dose- and time-dependent suppression of lordosis responding in ovariectomized guinea pigs treated with estradiol-17 beta and progesterone. The suppression of lordosis by morphine appears to be mediated by opiate receptors since the opiate antagonist naloxone blocked its effects both in terms of the percentage of animals showing lordosis and the duration of individual responses. Naloxone, when given alone, did not affect lordosis responding in estradiol-17 beta + progesterone-primed animals and did not induce lordosis in animals primed with estradiol-17 beta alone. Thus, endogenous opioids might not tonically inhibit lordosis under the physiological conditions examined. The alpha-noradrenergic agonist clonidine did not reverse the effects of morphine on lordosis. Thus, the inhibitory effects of morphine on this behavior might be independent of its presynaptic effects on norepinephrine release in brain.
阿片类激动剂吗啡对用17β-雌二醇和孕酮处理的去卵巢豚鼠的脊柱前凸反应产生剂量和时间依赖性抑制。吗啡对脊柱前凸的抑制作用似乎是由阿片受体介导的，因为阿片拮抗剂纳洛酮在表现出脊柱前凸的动物百分比和个体反应持续时间方面均阻断了其作用。单独给予纳洛酮时，对用17β-雌二醇+孕酮预处理的动物的脊柱前凸反应没有影响，对仅用17β-雌二醇预处理的动物也不会诱导脊柱前凸。因此，在所研究的生理条件下，内源性阿片类物质可能不会对脊柱前凸产生紧张性抑制作用。α-去甲肾上腺素能激动剂可乐定不能逆转吗啡对脊柱前凸的作用。因此，吗啡对这种行为的抑制作用可能与其对脑内去甲肾上腺素释放的突触前作用无关。
