INRA, UMR85 Physiologie de la Reproduction et des Comportements, Nouzilly, France.
J Neuroendocrinol. 2011 Nov;23(11):984-93. doi: 10.1111/j.1365-2826.2011.02203.x.
Profound behavioural changes occur in the mother at parturition, together with extensive remodelling of neural circuits. These changes include neurochemical, morphological and functional plasticity. The continuous generation of new neurones in the hippocampus and the olfactory system is an additional form of neuroplasticity that contributes to motherhood. This review describes the reciprocal relationships between hippocampal and olfactory neurogenesis and parental behaviour. Studies in rodents demonstrate that parturition and interactions with the young affect both cell proliferation and survival in a different manner across neurogenic zones. Species in which an individual recognition of the offspring is formed, such as sheep, show a down-regulation of neurogenesis during the perinatal period. This would function to decrease cell competition, favouring the selection of newborn neurones involved in olfactory recognition of the young. Also, in biparental species, increases in olfactory neurogenesis occur in the father in response to pup exposure during the early postpartum period. Oestradiol, corticosterone and prolactin changes associated with parturition are the main physiological factors involved in the regulation of neurogenesis that have been determined so far. In the father, prolactin mediates an enhancement of olfactory neurogenesis. Contradictory evidence indicates a functional link between neurogenesis and parenting behaviour. Mice receiving focal irradiation of the olfactory neurogenic subventricular zone show few disturbances in the expression of maternal behaviour, whereas a reduction of both hippocampal and olfactory neurogenesis as a result of the infusion of an anti-mitotic agent induces behavioural deficits. Disrupting prolactin signalling abolished increased paternal neurogenesis and offspring recognition by the father, and rescuing this neurogenesis restored recognition behaviour. More studies that selectively suppress the changes of neurogenesis are needed to confirm the role of new neurones in regulating parenting behaviour.
分娩时，母亲会发生深刻的行为变化，同时神经回路也会发生广泛的重塑。这些变化包括神经化学、形态和功能可塑性。海马体和嗅觉系统中新生神经元的持续产生是促进母性行为的另一种形式的神经可塑性。这篇综述描述了海马体和嗅觉神经发生与亲代行为之间的相互关系。在啮齿动物研究中，分娩和与幼崽的互动以不同的方式影响着不同的神经发生区域的细胞增殖和存活。在形成个体对后代识别的物种中，例如绵羊，在围产期会下调神经发生。这将有助于减少细胞竞争，有利于选择参与幼崽嗅觉识别的新生神经元。此外，在双亲物种中，雄性在产后早期接触幼崽时，嗅觉神经发生会增加。与分娩相关的雌激素、皮质酮和催乳素变化是迄今为止确定的调节神经发生的主要生理因素。在雄性中，催乳素介导嗅觉神经发生的增强。矛盾的证据表明神经发生和养育行为之间存在功能联系。接受嗅神经发生室下区局部辐照的小鼠在表达母性行为方面几乎没有受到干扰，而由于注入抗有丝分裂剂导致海马体和嗅觉神经发生减少会引起行为缺陷。破坏催乳素信号会消除雄性的父代神经发生和对后代的识别，而恢复这种神经发生则恢复了识别行为。需要更多选择性抑制神经发生变化的研究来确认新神经元在调节亲代行为中的作用。
