胆囊收缩素对大鼠催乳素释放的调节及其机理  

Effect of Cholecystokinin on Prolactin Release and Its Action Mechanism in the Rats

作　　者：周远征[1] 黄曼影[1] 单惠敏[1] 郭传海[1] 韩小四[1] 许荣[1] 

机构地区：[1]中国医学科学院,中国协和医科大学

出　　处：《中国医学科学院学报》1995年第6期412-417,共6页Acta Academiae Medicinae Sinicae

基　　金：国家自然科学基金;中国医学科学院基金

摘　　要：给清醒自由活动的大鼠第三脑室内微量注射０．０５和０．５μｇ胆囊收缩素（ＣＣＫ－８）观察到，可显著兴奋前叶垂体催乳素（ＰＲＬ）的静息分泌，并进一步促进限制性应激引起的ＰＲＬ释放。０．０５μｇＣＣＫ－８的上述两种作用较０．５μｇＣＣＫ－８的效应更强。在体外培养的前叶垂体细胞中，分别加入０．０５、０．５、１．０μｇＣＣＫ－８，孵育１ｈ，看到３种剂量的ＣＣＫ－８均显著兴奋ＰＲＬ释放，兴奋效应依ＣＣＫ－８的剂量增加而增大；２×１０－４ｍｏｌ／ＬＣＣＫ－８可使前叶垂体细胞的胞内Ｃａ２＋浓度显著升高，而１０－６～１０－８ｍｏｌ／Ｌ的ＣＣＫ－８不影响其胞内ｃＡＭＰ的含量。The effect of cholecystokinin octapeptide(CCK-8)on the release of prolactin (PRL) in male rats were studied in vivo and in vitro, CCK-8 at the concentrations(μg) of 0.05 and 0. 5 was injected into the third cerebral ventricle(3rd.V.I) of conscious rats, outfitted with chronic 3rd.V. and jugular cannulae, a significant increase in resting secretion and restraint stress-induced release of PRL were observed. The effects of CCK-8 at the concentration of 0. 05μg were stronger than those of 0. 5μg.To determine if CCK-8 would exert any direct action on anterior pituitary, CCK-8 of 0. 05,0.5,1. 00μg were added to the medium of dispersed anterior pituitary cell, and caused dose-dependent increase of PRL secretion. To study a mechanism of intracellular signal transduction in the action of CCK-8, the levels of cAMP and [Ca2+] in the medium were measured. Intracellular Ca2+ concentration of disperse anterior pituitary cell was significantly elevated by CCK-8(2 × 10-4mol/L),but CCK-8 (10-8-10-6mol/L) did not change intracellular cAMP content. The results indicate that CCK-8 stimulate prolactin release at both sites of hypothalamic and anterior pituitary and the mechanism of stimulating effects of CCK-8 might be mediated by[Ca2+] but not cAMP.

关 键 词：胆囊收缩素 催乳素 静息分泌 限制性应激 

分 类 号：R335[医药卫生—人体生理学]