Bolwerk E L, Swanson H H
J Endocrinol. 1984 Jun;101(3):353-7. doi: 10.1677/joe.0.1010353.
Oxytocin is released during parturition and may also play a role in maternal behaviour. Oxytocin, injected in the cerebral ventricles, has been reported to accelerate the onset of maternal behaviour in oestrogen-pretreated virgin Sprague-Dawley rats within 2 h of injection. This study was an attempt to replicate and extend these findings in Wistar rats. In the first experiment, 16 virgin females were ovariectomized and a cannula was placed into the cerebral ventricle. Forty-eight hours after a single injection of 24 micrograms oestradiol benzoate (OB), 400 ng oxytocin or saline were injected into the ventricle. In the second experiment three groups were observed: an untreated control group plus two ovariectomized and cannulated groups treated with OB in a regimen designed to mimic pregnancy. After 10 days of OB administration they received an injection of either saline or oxytocin (400 ng) into the ventricle. Immediately after this injection they were exposed to the pups and observations started. In both experiments no rat became maternal in the first 1.5 h after the intracerebroventricular injection. Oxytocin therefore did not induce a rapid onset of maternal responsiveness in oestrogen-pretreated Wistar rats.
催产素在分娩过程中释放，可能也在母性行为中发挥作用。据报道，向脑室注射催产素能使经雌激素预处理的未孕斯普拉格-道利大鼠在注射后2小时内加速母性行为的出现。本研究试图在Wistar大鼠中重复并扩展这些发现。在第一个实验中，将16只未孕雌性大鼠进行卵巢切除，并在脑室植入套管。单次注射24微克苯甲酸雌二醇（OB）48小时后，向脑室内注射400纳克催产素或生理盐水。在第二个实验中，观察了三组：一个未处理的对照组以及两个经卵巢切除并植入套管的组，这两组用一种旨在模拟怀孕的方案给予OB处理。给予OB 10天后，它们接受向脑室内注射生理盐水或催产素（400纳克）。在这次注射后立即让它们接触幼崽并开始观察。在两个实验中，没有一只大鼠在脑室内注射后的前1.5小时内表现出母性行为。因此，催产素不会在经雌激素预处理的Wistar大鼠中迅速诱发母性反应。
