雌性大鼠下丘脑脑啡肽含量的增龄性变化及其对血清黄体生成素水平的影响

本实验测定了老年,成年和年轻雌性Wistar大鼠下丘脑甲硫氨酸脑啡肽(MEK)、亮氨酸脑啡肽(LEK)、血清黄体生成素(LH)的含量;并于侧脑室分别注射吗啡、纳洛酮加吗啡、酚妥拉明加纳洛酮后。观察血清LH的变化。结果表明,随着增龄,下丘脑脑啡肽(EK)含量明显升高;年轻和成年大鼠血清LH水平明显高于老年大鼠。侧脑室注射吗啡后,血清LH明显下降;注射纳洛酮后再注射吗啡,血清LH明显升高;注射酚妥拉明后再注射纳洛酮,血清LH水平显著下降。本实验结果表明,EK调节LH的分泌,并且是在去甲肾上腺素参与下完成的。作者认为,大鼠下丘脑EK含量的随龄增高可能与其下丘脑—垂体—性腺轴的老化有一定的关系。

Age-Related Changes of Enkephalin level in Hypothalamus of Female Rat and Ite Influence on Serum Luteinizing Hormon Level

Serum met-enkedhalin,leu-enkephalin and luteinizing hormone(LH) were measured in old, mature and young female wistar rats, and after the injection of morphine, naloxone plus morphine, phentolamine plus naloxone respectively into the lateral ventricles. The increase in EK levels were higher in old rats, but significantly decreased after the injection of morphine into lateral ventricles and ineresed after the injection of morphine following nalozone, while the injection of naloxone following phentolamine caused the serum LH to decline markedly. It indicates that EK regulates the LH secretion with participation of norepinephrine. The age-related increase in EK in hypothalamus might be associated with aging of hypothalamicpituitarygonadal axis.