Injection of hypertonic saline or mannitol accelerates the dehydration-induced activation of dopamine synthesis in the neurointermediate lobe of the rat hypophysis.
Injection of hypertonic saline or mannitol accelerates the dehydration-induced activation of dopamine synthesis in the neurointermediate lobe of the rat hypophysis.
复制标题
注射高渗盐水或甘露醇可加速大鼠垂体神经中叶中脱水诱导的多巴胺合成激活。
DOI：
10.1159/000123424
复制
发表时间：
1982
影响因子：
4.1
通讯作者：
Moore,KE
中科院分区：
文献类型：
--
作者：
Alper,RH;Moore,KE
在渗透刺激后的不同时间，测定了大鼠垂体神经中间叶（NIL）中垂体结节DA神经元末端多巴胺（DA）的合成速率（在给予芳香l -氨基酸脱羧酶抑制剂后多巴胺的积累）。注射高渗生理盐水（5 ml 15% NaCl/kg, s.c）后24 h，而非4 h，如果动物在注射后不允许喝水，NIL中DA合成增加，但中隆起或纹状体中DA合成没有增加；24 h的缺水对DA的合成速率没有影响。静脉输注甘露醇（25 ml 20%甘露醇/kg）加24小时缺水后，NIL中的DOPA积累也增加。这些结果表明，脱水诱导的垂体结节DA神经元的激活通常在缺水2-3天后出现，如果在缺水之前注射高渗盐水或甘露醇，脱水诱导的激活可以加速。
The rate of dopamine (DA) synthesis (DOPA accumulation after the administration of an inhibitor of aromatic L-amino acid decarboxylase) was determined in terminals of tuberohypophyseal DA neurons in the neurointermediate lobe (NIL) of the rat hypophysis at various times after the presentation of osmotic stimuli. DA synthesis in the NIL, but not in median eminence or striatum, was increased 24 h but not 4 h after an injection of hypertonic saline (5 ml 15% NaCl/kg, s.c), provided the animals were not permitted access to water after the injection; 24 h of water deprivation per se was without effect on the rate of DA synthesis. DOPA accumulation in the NIL was also increased after an intravenous infusion of mannitol (25 ml 20% mannitol/kg) plus 24 h of water deprivation. These results suggest that the dehydration-induced activation of tuberohypophyseal DA neurons which is normally seen after 2–3 days of water deprivation can be accelerated if water deprivation is preceeded by injections of hypertonic saline or mannitol.