Muraki T, Tokunaga Y, Nakadate T, Kato R
Arch Int Pharmacodyn Ther. 1980 Aug;246(2):324-34.
A single administration of morphine reduced both serum LH and FSH levels in castrated Wistar rats. As the inhibitory effect of morphine on serum LH was antagonized by naloxone, the opiate receptors are involved. Decrease in the serum FSH levels induced by morphine was considerably less than the decrease in serum LH, and naloxone did not significantly reverse this effect of morphine on serum FSH. Increase in the serum LH induced by exogenous LHRH was slightly potentiated and not inhibited by a large dose of morphine, in both intact and castrated rats. Increase in the serum FSH in intact male rats induced by exogenous LHRH was not altered by morphine. In the castrated animals, exogenous LHRH did not further increase the serum FSH levels and the latter was not altered by a concomitant administration of morphine. These results clearly show that the decrease in serum gonadotropin levels by morphine is not due to inhibition of the stimulatory effect of LHRH on the pituitary gland. The mechanism of the differential suppression on serum LH and FSH by morphine is postulated.
单次注射吗啡可降低去势Wistar大鼠的血清促黄体生成素（LH）和促卵泡生成素（FSH）水平。由于纳洛酮可拮抗吗啡对血清LH的抑制作用，表明阿片受体参与其中。吗啡诱导的血清FSH水平下降明显小于血清LH的下降，且纳洛酮不能显著逆转吗啡对血清FSH的这种作用。在外源性促性腺激素释放激素（LHRH）诱导血清LH升高的情况下，完整大鼠和去势大鼠注射大剂量吗啡后，血清LH升高均稍有增强而非受到抑制。外源性LHRH诱导的完整雄性大鼠血清FSH升高不受吗啡影响。在去势动物中，外源性LHRH不会进一步升高血清FSH水平，同时注射吗啡也不会改变血清FSH水平。这些结果清楚地表明，吗啡导致血清促性腺激素水平下降并非由于抑制LHRH对垂体的刺激作用。本文推测了吗啡对血清LH和FSH产生不同抑制作用的机制。
