大鼠室旁核内催产素免疫阳性细胞树突棘样结构在脱水状态下的改变

树突棘，室旁核，催产素，脱水，免疫组化，大鼠下丘脑内催产素大细胞神经分泌细胞与水盐代谢的调节有关，并伴有细胞形态的改变如细胞体积的增大及细胞膜与细胞膜间接触的增加和多突触的形成等。本文用免疫组化法发现在脱水状态下室旁核的催产素免疫阳性神经元上树突棘样结构有所增加。光镜观察并计算室旁核前大细胞亚核、内侧大细胞亚核及后大细胞亚核中含树突棘样结构的催产素神经元百分数变化，显示正常大鼠室旁核神经元树突棘样结构多位于树突干上，少数在胞体上。前大细胞亚核含树突棘样结构的细胞百分数为２１．２７％，内侧大细胞亚核为３０．２２％，后大细胞亚核为２０．２２％。轻度脱水大鼠室旁核含树突棘样结构细胞百分数显著增加（前大细胞亚核：２８．６５％，Ｐ＜０．０５；内侧大细胞亚核：３５．５３％，Ｐ＞０．０５；后大细胞亚核：３４．７８％，Ｐ＜０．０１）。细胞上树突棘样结构数也增加，其体积略为增大。重度脱水大鼠室旁核中树突棘样结构细胞百分数增加较小，仅后大细胞亚核内有显著变化（２７．１３％，Ｐ＜０．０５）。不同程度脱水组之间无显著变化。结果说明脱水可引起神经元膜结构的改变。树突棘样结构数变化是否与新突触的形成有直接关系？尚待进一步证实。

CHANGES OF SPINE-LIKE STRUCTURES ON OXYTOCINE-LIKE IMMUNOREACTIVE CELLS IN THE PARAVENTRICULAR NUCLEUS DURING DEHYDRATION IN THE RAT

Immunohistochemical method was used to study the changes of spine-like strurtures (SLS) on Oxytocine-like immunoreactive (OXT-LI) cells in the paraventricular nucleus (PVN) in rat during dehydration. It were found that both the number of SLS on the OXT-LI cells and the percentage of the OXT-LI cells which had SLS increased in some level after slight dehydration (D1) and heavy dehydration (D2). In D1. the percentages of 3 subdivision of PVN were markly increased vs the control ones: anterior magnocellular PVN (amPVN) 28. 65% vs 21. 27% P<0. 05; medial magnocellular PVN (mmPVN), 35. 53% vs 30. 27% . P>0. 05; posterior magnocellular PVN (pmPVN), 34. 78% vs 20. 22% .P<0.01. In D2 . the percentages increased slightly vs control ones . only the one of pmPVN significantly elevated : 27. 13% vs 20. 22%.The percentages between D1 and D2 had no significant changes. The result demonstrated that dehydration could cause the plastic transformation of the important membrane structures. Whether this change responded to the formation of new synapses remains to be studied.