Keverne E B, Kendrick K M
Sub-Department of Animal Behaviour, Cambridge, U.K.
Brain Res. 1991 Feb 1;540(1-2):55-62. doi: 10.1016/0006-8993(91)90492-e.
The effects of intracerebroventricular infusions of morphine, oxytocin, and corticotrophin-releasing factor (CRF) on maternal behaviour alone, or in conjunction with vaginocervical stimulation were determined in both nulliparous and multiparous ovariectomized ewes, primed with oestrogen for 3 days prior to testing. Both plasma and cerebrospinal fluid levels of oxytocin were measured under similar conditions, following CRF and morphine treatments. In nulliparous ewes, i.c.v. oxytocin and morphine reduced rejection behaviours, but neither these treatments nor vaginocervical stimulation promoted proceptive acceptance behaviour. Ewes that were maternally experienced showed increases in acceptance and a reduction of rejection behaviours following vaginocervical stimulation or i.c.v. oxytocin. Morphine and CRF potentiated the effects of vaginocervical stimulation on these behaviours. No treatment influenced oxytocin release per se, but i.c.v. morphine increased both peripheral and central release of oxytocin in response to vaginocervical stimulation. The results show that maternal experience is essential for oxytocin to promote proceptive behaviours and that morphine and CRF potentiate the effects of vaginocervical stimulation on acceptance behaviour. Since morphine also potentiated the release of oxytocin in response to vaginocervical stimulation it is difficult to separate the relative contribution of direct versus indirect effects of opiates in potentiating maternal bonding.
在未产和经产的去卵巢母羊中，于测试前用雌激素预处理3天，测定脑室内注入吗啡、催产素和促肾上腺皮质激素释放因子（CRF）单独或与阴道子宫颈刺激联合作用对母性行为的影响。在CRF和吗啡处理后，于相似条件下测量催产素的血浆和脑脊液水平。在未产母羊中，脑室内注入催产素和吗啡可减少排斥行为，但这些处理以及阴道子宫颈刺激均未促进接受行为。有母性经验的母羊在阴道子宫颈刺激或脑室内注入催产素后，接受行为增加，排斥行为减少。吗啡和CRF增强了阴道子宫颈刺激对这些行为的影响。没有处理本身影响催产素释放，但脑室内注入吗啡可增加阴道子宫颈刺激引起的外周和中枢催产素释放。结果表明，母性经验对于催产素促进接受行为至关重要，并且吗啡和CRF增强了阴道子宫颈刺激对接受行为的影响。由于吗啡也增强了阴道子宫颈刺激引起的催产素释放，因此难以区分阿片类药物在增强母婴联结中的直接和间接作用的相对贡献。
