摘要
目的探索季节变化对大鼠性腺轴褪黑素(MT)受体的影响及其生理机理。方法采用大鼠松果体摘除模型,运用放射性配基饱和法,测定雄性SD大鼠性腺轴褪黑素受体的最大结合量(Bmax)和解离常数(Kd值)的冬夏变化。结果在正常生理条件下,下丘脑和垂体褪黑素受体Bmax值(P<0.05)、Kd值(P<0.01)均表现为冬高夏低。摘除松果体后,除了垂体夏季手术组Bmax值与正常对照组相比没有明显变化(P>0.05),冬、夏季节下丘脑、垂体手术组Bmax值和Kd值都明显高于相应的正常对照组(P<0.01)。而睾丸的褪黑素受体因含量极少而无法测出其与125I-MT特异性结合的Bmax值和Kd值。结论下丘脑、垂体褪黑素受体具有明显的季节性节律变化,松果体可能在此过程中起重要的调节作用。
Objective： To explore the seasonal effect on melatonin receptor in rat＇s hypothalamus-pituitary-gonad （HPG） axis.
Methods： The animals were divided into two groups： normal group and pinealectomy group. For the detection of melatonin receptor, radioligand saturation was employed.
Results： Bmax and Kd of melatonin receptor in normal rat＇s hypothalamus and pituitary in winter were significantly higher than those in summer （P〈0.05 and P〈0. 01, respectively）, and the values of Bmax and Kd in pinealectomized rats showed the same pattern except Bmax of hypothalamus in summer. Both summer and winter values of Bmax and Kd of the receptor in pinealectomized rat＇s hypothalamus and pituitary were significantly higher than those of the control group （P〈0. 01）. The value of Bmax and Kd in rat＇s testes can not be determined since the extremely low level of melatonin receptor.
Conclusions： There are significant seasonal changes of rat＇s melatonin receptor at HPG axis and the pineal gland plays an important role in its regulation.
出处
《生殖医学杂志》
CAS
2006年第1期38-41,共4页
Journal of Reproductive Medicine
基金
国家自然科学基金资助项目(3977088830472113)
关键词
季节
下丘脑
垂体
褪黑素受体
Season
Hypothalamus
Pituitary
Melatonin receptor
