Kekki M, Attila U, Talanti S
Cell Tissue Res. 1975 May 20;158(4):439-50. doi: 10.1007/BF00220211.
Thirst stimulation of the supraoptic nucleus (SON) and paraventricular nucleus (PVN) was induced in rats by withholding all fluids during three days. 35S-cysteine was then intraperitoneally administered and the rats were killed at predetermined times and examined by autoradiography, applying the authors' previously described method. This experimental series totalling 51 animals was compared with a control series of 70 rats, similarly treated, who had had free access to water. The kinetic phenomena in SON and PVN were analysed in terms of the two-compartment model previously used, which gives an estimate of the neurosecretory material (NSM) secretion parameters and of those of the lumped structural cell protein turnover in the nuclei. The kinetics of the precursor amino acids after administration of labelled cysteine were also assessed. Determinations of the label uptake at two specific times in the experiment, in the infundibular nucleus, ventromedial nucleus and optic nerve tissue in both series served as a check on the specifity of the structural protein turnover changes observed. Compared with the controls, the turnover rate of the slow compartment was more than tripled in the dehydrated rats, while that of the fast compartment had gone down to about one-third; both effects very nearly equal in SON and PVN. These results are compatible with the concept according to which thirst stimulates the SON and PVN equally. A distinct, and strikingly equal, hump was observed (2 hours after label administration) in all specific activity curves, also in the precursor serum concentration, and it is probably due to recycling of 35s from cysteine to methionine. This and other circumstances render the phenomena rather too complex for a straight-forward evaluation by the two-compartment model. Even so, the observations are believed to furnish good evidence of the biological verity of this model as well as the thirst-induced changes elicited.
通过在三天内不给大鼠提供任何液体来诱导视上核（SON）和室旁核（PVN）的渴觉刺激。然后腹腔注射35S-半胱氨酸，并在预定时间处死大鼠，采用作者先前描述的方法进行放射自显影检查。将这个总共51只动物的实验系列与一个同样处理但可自由饮水的70只大鼠的对照系列进行比较。根据先前使用的两室模型分析SON和PVN中的动力学现象，该模型可估计神经分泌物质（NSM）的分泌参数以及核中集总结构细胞蛋白质周转的参数。还评估了给予标记半胱氨酸后前体氨基酸的动力学。在两个系列的实验中，在特定时间测定漏斗核、腹内侧核和视神经组织中的标记摄取量，以检查所观察到的结构蛋白周转变化的特异性。与对照组相比，脱水大鼠慢室的周转率增加了两倍多，而快室的周转率下降到约三分之一；在SON和PVN中这两种效应几乎相等。这些结果与渴觉同等刺激SON和PVN的概念相符。在所有比活度曲线以及前体血清浓度中都观察到一个明显且惊人相等的峰（标记给药后2小时），这可能是由于35S从半胱氨酸循环到蛋氨酸所致。这种情况以及其他因素使得这些现象对于用两室模型进行直接评估来说过于复杂。即便如此，这些观察结果被认为充分证明了该模型的生物学真实性以及渴觉诱导的变化。
