子宮運動에 미치는 Epinephrine 및 Norepinephrine의 作用과 卵巢「홀몬」과의 相關性에 關한 實驗的硏究
(The) influence of ovarian hormones on the response to epinephrine or norepinephrine of rabbit uter
It is well known fact that uterine motility is consistently influenced by ovarian hormones and that the catecholamine content of the uterus is also altered by these hormones. Wurtman et al.(1963) reported that the endogenous eqpinephrine content of
uterus increased during estrus and also noted that the endogenous epinephrine content of uterus increased during estrus and also noted that the uptake of tritiated epinephrine during estrus was significantly increased in the rat.
Furthermore, Snyder et al.(1964) postulated that there is a cyclic variation in uterine epinephine content during estrus cycle. These findings are also supported by Cha et al. (1965) who observed that prolonged administration of estrogen increases, whereas progesterone decreases the epinephrine content of the organ.
Although a considrsble number of reports concerning the changes of uterine catecholamine content in relation to various hormonal influences have been appeared in recent years, little is known about the role of these hormones in the activities of catecholamines on uterine motility. Grunber (1993) stated stated that epinephrine stimulated the rabbit uterus in either the pregnant or the nonprognant state, whereas the uterus of rat always responds to sympathomimetics with relaxation regardless of whether the rats are in setrus or diestrus. Subsequent stueies of Gunn (1942), Titus (1937) and Garret (1954), revealed that the response of the uterus to catecholamines varied with the species and with the hormonal state of the animals. Recently Tsai and Fleming (1964) strongly postulated that the changes in response to catecholamine of the uterus correlated with hormonal alteration are due to a shift in the balance of the receptors. This finding is consistent with the results of Roh (1966) sho observed that the effect of catecholamines on the uterine activity was first inhibitory on the early pergnancy but bec��gradually stimulative as the pregnancy progressed. In view of the above controversial reports it is suggested that there seems to be some relation between the activity of catecholamines and the hormonal changes. The present study was, therefore, undertaken to explore the activity of catecholamines on the uterine motility in relation to ovarian hormones.
Female albino rabbits weighing approximately 2.0kg were employed in this experiment. At the end of ted days following cophorectomy, the animals were injected intramusculary with estrohen (4,0000 i.u.) or progesterone (10mg) daily for 4 day.
Uterine strips were prepared and they were suspended in a constant temperature bath(38。C) containing 100ml of Lock's solution aerated with 95% oxygen and 5% carbon dioxide. Spontaneous motility was recorded on a smoked drum with an isotonic lever. The epinephrine and norepinephrine content of the uteri was determined according to the procudure descirbed by Shore and Olin(1958).
Results and Discussion
1. Bilateral oophorectomy of adult rabbits results in a marked shrink of the uterus in size. The spontaneous motility of the uterine segment of these animals was very weak and irregular. Norepinephrine produced inhibitory effec, whereas epinephrine stimulatory or inhibitory effect on the uterine segment. The total catecholamine content in whole uterus was markedoy reduced and the amounts of epinephrien and norepinephrine were 221mμg/uterus, and 992mμg/uterus, respectively.
2. The injection of estogen into the oophrectomized rabbit increased the weight of uterus to approximately three times of the of oophorectomized animals. The spontaneous motility and the response to epinephren and norepinephrine of the uterine segment were greatly enhanced. Both epinephrine and norepinephrine produced a made stimulatory effects on the uterine motility. The uterine content of catecholamines, particurly of epinephrine was markedly increased. The amounts of epinephrine and norepinephrine in whole uterus were 731 mμg, and 1597 mμg, respectively.
3. The injection of progesterone into the oophorectomized rabbit increased the weight of uterus to approximately 2.5 times of that of oophorectomized animal. The spontaneous motility of the uterine segment was weak and irregualr. Epinephrine produced stimulatory effect at high concentrations but norepinephrien always produced inhibitory effect on the uterine segment. The uterine content of catecholamines, particularly of norepinephrine was markedly reduced. The total contents of eqinephrine and norepinephrine in whole uterus were 359 mμg and 634 mμg, respectively.
4. The administration of estrogen for 4 days following the injection of rpogesterone into the oophorectomized rabbit rendered the uterus to respond epinephrine and norepinephrine similar to that of estrogen-treated oophorectomized rabbits. The total uterine contents of epinephrine and norepinephrine were 534 mμg and 687 mμg, respectively.
On the contrary, the administration of progesterone for 4 days following the injection of estrogen into the oophorectomized rabbtis rendered the uterus to respond to epinephrine and norepinephrine similar but more markedly that of progesterone treated oophorectomized rabbits. The total uterine contents of
epinephrine and norepihephrine were 675.5mμg and 962.5 mμg, respectively.
5. The combined administration of reserpine with estrogen or progesterone into the oophorectomized rabbit markedly decreased but not completely the uterine content of catecholamines. The stimulatory response to epinephrine and norepinephrine of the uterine segment was reduced, whereas the inhibitory response
to these catecholamines appeared to be enhanced.
From the above results it is clear that ovarian hormones play an important role not only on the growth and spontaneous motility of uterus but also on the catecholamine content and response to epinephrine and norepinephrine of the uterus.
Estrogen increases uterine catecholamines particulary epinephrien content and enhances the stimulatory response to epinephrien and norepinephrine of the uterus, whereas progesterone decreases uterine catecholamines, particulary norepinephrine content and enhances the inhibitory response to epinephrien and norepinephrine of the uterus.