Higuchi T, Honda K, Negoro H
J Endocrinol. 1986 Aug;110(2):245-50. doi: 10.1677/joe.0.1100245.
The influence of oestrogen on LH and oxytocin responses to immobilization stress, and the involvement of noradrenergic afferent neurones in these responses, was examined in ovariectomized rats with or without pretreatment with oestrogen or after noradrenergic transmitter blockade. Immobilization of the rats on a board in a supine position for 1 h brought about a rapid decrease in LH levels and an increase in oxytocin levels in the blood of ovariectomized rats. Oestradiol benzoate (20 micrograms) injected s.c. the day before immobilization, decreased basal LH levels but had no effect on basal oxytocin levels. Immobilization stress applied to oestrogen-treated rats induced a small but significant increase in LH concentrations and a rise in oxytocin concentrations similar to that in rats without oestrogen pretreatment. A dopamine-beta-hydroxylase inhibitor or phenoxybenzamine (alpha-adrenoceptor blocker) injected into ovariectomized rats reduced basal LH levels and increased basal oxytocin levels in the blood. Immobilization stress induced an increase in LH levels in rats treated with dopamine-beta-hydroxylase inhibitor, but had no effect in rats treated with phenoxybenzamine. Stress induced a larger increase in blood oxytocin levels in rats treated with either drug compared with that in control rats injected with vehicle. On the other hand, propranolol (beta-adrenoceptor blocker) had no effect on basal or stress-induced changes in LH or oxytocin levels in the blood. These results indicate that the LH response to stress, which might be mediated through alpha-adrenergic neurones, depends on the circulating oestrogen or LH levels before the stress. In contrast, the oxytocin response to stress may not be mediated by noradrenergic neurones and may not be influenced by oestrogen.
研究了雌激素对去卵巢大鼠在固定应激下促黄体生成素（LH）和催产素反应的影响，以及去甲肾上腺素能传入神经元在这些反应中的作用。实验对象为去卵巢大鼠，分别在有或无雌激素预处理的情况下，以及在去甲肾上腺素能递质阻断后进行实验。将大鼠仰卧固定在板上1小时，导致去卵巢大鼠血液中LH水平迅速下降，催产素水平升高。在固定前一天皮下注射20微克苯甲酸雌二醇，可降低基础LH水平，但对基础催产素水平无影响。对雌激素处理的大鼠施加固定应激，可诱导LH浓度小幅但显著升高，催产素浓度升高，与未进行雌激素预处理的大鼠相似。向去卵巢大鼠注射多巴胺-β-羟化酶抑制剂或酚苄明（α-肾上腺素能受体阻滞剂），可降低血液中的基础LH水平，并升高基础催产素水平。固定应激可使注射多巴胺-β-羟化酶抑制剂的大鼠LH水平升高，但对注射酚苄明的大鼠无影响。与注射溶剂的对照大鼠相比，两种药物处理的大鼠应激诱导的血液催产素水平升高幅度更大。另一方面，普萘洛尔（β-肾上腺素能受体阻滞剂）对血液中基础或应激诱导的LH或催产素水平变化无影响。这些结果表明，LH对应激的反应可能通过α-肾上腺素能神经元介导，取决于应激前的循环雌激素或LH水平。相比之下，催产素对应激的反应可能不是由去甲肾上腺素能神经元介导的，也可能不受雌激素影响。
