Fidelina O V, Gorbatiuk O S, Adamskaia E I, Akmaev I G
Institute of Experimental Endocrinology, Endocrinology Research Centre, Moscow.
Usp Fiziol Nauk. 1999 Apr-Jun;30(2):41-9.
The investigation was performed on the medial (MMS) and lateral (LMS) magnocellular subdivisions of the hypothalamic paraventricular nuclei (HPN). The histochemical activity NO synthesizing enzyme nitric oxide synthase or NOS whose histochemical marker is NADPH-diaphorase (NADPH-D), immunocytochemical content of oxytocin (OXY), vasopressin (VP) and nucleoli sizes (squares) were studied in the mature male rats under experimental reconstruction of the both micro- and macrogravity, which are factors of the gravity field changes acting to the body during the space flight. Two experimental effects were used: B--tail suspending (imitation of the microgravity effects), C--centrifugation at 2 G (imitation of the macrogravity effects). The effect durations were designed as a time period when body is mostly affected by (1 day) and adapted (15 days) to the stress. There were 6 animal groups. 1--B(15 days), 2--B(15 days) succeeded by C(1 day), 3--B(15 days) succeeded by C(15 days), 4--C(1 day), 5--C(15 days), 6--intact animals. The histochemically and immuno-cytochemically stained neurons developing the high, moderate and small reaction intensity were counted in serial HPN sections under the light microscope and the results obtained were transformed to percent neuron contents. The nucleoli squares were examined by using the TV analyser. The histochemical staining intensity of NADPH-D in MMS is enhanced in the animals of the groups 1-4; the number of NADPH-D staining neurons with high enzyme activity was increased in 8-14 times. In the animals of group 5 the NADPH-D activity did not differ from the intact animals. The number of MMS neurons with high OXY immunoreactivities was increased up to 1.5-1.7 times in groups 1-5 if compared to those of intact controls. VP-positive neurons of LMS developed the similar increase in number of the high staining neurons in experimental animals as well as OXY-positive neurons of MMS. The nucleoli enlargement was observed in MMS (in 1.3-1.5 times) of groups 1-5 (insignificantly in group 5) and in the most magnocellular neurons LMS (in 1.5-1.7 times) of group 2-5 except group 1 where nucleoli were insignificantly decreased. The nucleoli sizes of group 4 were more than group 5. So the hypothalamo-neurohypophyseal system was activated in the animals subjected of the earthly correlates of micro- and macrogravity. The data obtained suggest involvement both the nonconventional neurotransmitter NO and stress-related peptides OXY and VP in the mechanisms subserving adaptation to the extreme factors by what a human has to be faced with during the space flight.
本研究针对下丘脑室旁核（HPN）的内侧（MMS）和外侧（LMS）大细胞亚群展开。在成熟雄性大鼠身上，研究了以烟酰胺腺嘌呤二核苷酸磷酸 - 黄递酶（NADPH - D）为组织化学标志物的一氧化氮合酶（NOS）的组织化学活性、催产素（OXY）和血管加压素（VP）的免疫细胞化学含量以及核仁大小（方块），实验模拟了微重力和大重力这两种在太空飞行期间作用于身体的重力场变化因素。采用了两种实验效应：B——尾部悬吊（模拟微重力效应），C——2G离心（模拟大重力效应）。效应持续时间设定为身体受影响最大（1天）并适应（15天）应激的时间段。共有6组动物。1——B（15天），2——先B（15天）后C（1天），3——先B（15天）后C（15天），4——C（1天），5——C（15天），6——完整动物组。在光学显微镜下，对HPN连续切片中呈现高、中、低反应强度的组织化学和免疫细胞化学染色神经元进行计数，并将所得结果换算为神经元含量百分比。使用电视分析仪检查核仁方块。MMS中NADPH - D的组织化学染色强度在第1 - 4组动物中增强；酶活性高的NADPH - D染色神经元数量增加了8 - 14倍。第5组动物的NADPH - D活性与完整动物组无差异。与完整对照组相比，第1 - 5组中具有高OXY免疫反应性的MMS神经元数量增加了1.5 - 1.7倍。LMS中VP阳性神经元的高染色神经元数量在实验动物中也有类似增加，MMS中OXY阳性神经元亦是如此。在第1 - 5组的MMS中观察到核仁增大（1.3 - 1.5倍）（第5组不明显），在第2 - 5组的大多数大细胞神经元LMS中核仁增大（1.5 - 1.7倍），第1组核仁略有减小。第4组的核仁大小大于第5组。因此，在经历地球微重力和大重力相关模拟的动物中，下丘脑 - 神经垂体系统被激活。所得数据表明，非常规神经递质NO以及与应激相关的肽OXY和VP均参与了机体适应太空飞行期间人类必须面对的极端因素的机制。
