Domínguez R, Riboni L, Zipitría D, Revilla R
J Endocrinol. 1982 Nov;95(2):175-80. doi: 10.1677/joe.0.0950175.
Rats with a 4-day oestrous cycle were given a single dose of atropine (100, 300, 500 or 700 mg/kg body wt) at 13.00 h on the days of oestrus, dioestrus 1, dioestrus 2 or pro-oestrus and were autopsied on the next expected day of oestrus. The doses of atropine (in mg/kg body wt) necessary to block ovulation during the cycle were 300 at oestrus, 100 at dioestrus 1 or 2 and 700 at pro-oestrus. A single dose of atropine (100 mg/kg) at oestrus, dioestrus 1 or dioestrus 2 was given at 09.00, 13.00, 17.00 or 21.00 h, autopsy again being performed on the next expected day of oestrus. The ability of atropine to block ovulation appeared to have a circadian rhythm, with a maximum blockade at 13.00 h on dioestrus 1 and dioestrus 2 and a minimum at 21.00 h on the same days. Hormone replacement (human chorionic gonadotrophin at oestrus, dioestrus 1 or 2, oestradiol benzoate at dioestrus 2 or progesterone at pro-oestrus) re-established normal ovulation in rats whose ovulation was blocked with atropine (100 mg/kg) on dioestrus 1 at 13.00 h. When ovulation was blocked with atropine but no hormone replacement had been given, rats ovulated 24 h after the next expected day of oestrus. Results obtained in these experiments suggest the existence of a circadian rhythm of gonadotrophin secretion throughout the oestrous cycle and a close relationship between that rhythm and the cholinergic system.
对处于4天发情周期的大鼠，在发情期、间情期1、间情期2或发情前期的13:00给予单次剂量的阿托品（100、300、500或700mg/kg体重），并在下次预期发情日进行解剖。在发情周期中阻断排卵所需的阿托品剂量（mg/kg体重）分别为：发情期300、间情期1或2为100、发情前期为700。在发情期、间情期1或间情期2的09:00、13:00、17:00或21:00给予单次剂量的阿托品（100mg/kg），同样在下次预期发情日进行解剖。阿托品阻断排卵的能力似乎具有昼夜节律，在间情期1和间情期2的13:00阻断作用最强，同一天的21:00阻断作用最弱。激素替代（发情期、间情期1或2用人绒毛膜促性腺激素，间情期2用苯甲酸雌二醇，发情前期用孕酮）可使在间情期1的13:00用阿托品（100mg/kg）阻断排卵的大鼠恢复正常排卵。当用阿托品阻断排卵但未给予激素替代时，大鼠在下次预期发情日后24小时排卵。这些实验结果表明，在整个发情周期中存在促性腺激素分泌的昼夜节律，且该节律与胆碱能系统之间存在密切关系。
