Hammkr R P
Department of Anatomy and Reproductive Biology, University of Hawaii School of Medicine, 1960 East-West Road, Honolulu, HI 96822, U.S.A.
Int J Dev Neurosci. 1985;3(5):541-8. doi: 10.1016/0736-5748(85)90043-7.
Opiate receptor labeling was examined throughout the early postnatal period using autoradiography to localize and quantify [(3)H]naloxone binding to μ-type opiate receptors in the medial preoptic area (MPOA). This region begins to exhibit sexual dimorphism of volume and dendritic growth shortly after birth. A distinct concentration of opiate receptor labeling appears on postnatal day 3 in females: this labeling is directly associated with the sexually dimorphic nucleus of the preoptic area (SDN-POA). SDN-POA labeling becomes denser through postnatal day 10 in females and the densely labeled area increases in size to encompass and surround the SDN-POA. These changes in opiate receptor labeling occur only in females, since males show relatively uniform labeling across the region throughout the early postnatal period. The critical time of formation of dense MPOA opiate receptor labeling may be related to endogenous MPOA opioid function and to the critical period of dendritic growth of SDN-POA neurons. The timing of these critical periods and their focus in the SDN-POA are coincident. The possible role of MPOA opiate receptors in modulating growth of MPOA neurons is discussed.
在出生后早期，使用放射自显影技术对阿片受体标记进行了检查，以定位和定量[³H]纳洛酮与内侧视前区（MPOA）中μ型阿片受体的结合。该区域在出生后不久就开始表现出体积和树突生长的性别二态性。在出生后第3天，雌性动物的阿片受体标记出现明显集中：这种标记与视前区性二态核（SDN-POA）直接相关。在雌性动物中，SDN-POA标记在出生后第10天变得更加密集，并且密集标记区域的大小增加，以包围和环绕SDN-POA。阿片受体标记的这些变化仅发生在雌性动物中，因为雄性动物在出生后早期整个区域的标记相对均匀。MPOA中密集的阿片受体标记形成的关键时间可能与内源性MPOA阿片类物质功能以及SDN-POA神经元树突生长的关键时期有关。这些关键时期的时间及其在SDN-POA中的焦点是一致的。讨论了MPOA阿片受体在调节MPOA神经元生长中的可能作用。
