Effects of In Vitro Anoxia and Low pH on Acetylcholine Release by Rat Brain Synaptosomes
Effects of In Vitro Anoxia and Low pH on Acetylcholine Release by Rat Brain Synaptosomes
复制标题
体外缺氧和低 pH 对大鼠脑突触体释放乙酰胆碱的影响
作者：
J. Sánchez;S. Harvey;J. Clark
摘要：在模拟缺氧损伤的各种条件下，包括低pH值（6.2）和存在乳酸盐和丙酮酸盐作为底物的条件下，使用胆碱-cent技术测量了大鼠脑突触体的乙酰胆碱和胆碱释放。乳酸盐加丙酮酸盐作为底物始终比单独的葡萄糖提供更高的呼吸速率，但是对于任一底物（葡萄糖或乳酸盐加丙酮酸盐），省略Ca 2+引起呼吸增加，而低pH引起呼吸降低。在对照条件（葡萄糖，pH 7.4）下的乙酰胆碱释放是Ca 2+依赖性的，由高K+浓度刺激，在缺氧期间显著降低，但在缺氧后一段时间的氧合后完全恢复。低pH值（6.2）抑制K+刺激乙酰胆碱释放，在低pH值缺氧一段时间后，乙酰胆碱释放的恢复只是部分的。以乳酸和丙酮酸为底物，缺氧和/或低pH对乙酰胆碱释放及其随后的恢复的影响加剧。胆碱从突触体释放，但是，不受缺氧/离子条件下的乙酰胆碱释放相同的方式。在低pH值（6.2）有一个显着减少胆碱释放在有氧和缺氧条件下。这些结果表明，乙酰胆碱释放本身的神经是非常敏感的缺氧的侮辱和缺氧过程中发生的低pH值可能是一个重要的促成因素。
Abstract: Acetylcholine and choline release from rat brain synaptosomes have been measured using a chemilumines‐cent technique under a variety of conditions set up to mimic anoxic insult, including conditions of low pH (6.2) and the presence of lactate plus pyruvate as substrate. Lactate plus pyruvate as substrate consistently gave higher respiration rates than glucose alone, but with either substrate (glucose or lactate plus pyruvate) the omission of Ca2+ caused an increase in respiration whereas a low pH caused a decreased respiration. Acetylcholine release under control conditions (glucose, pH 7.4) was Ca2+‐dependent, stimulated by high K+ concentrations, and decreased significantly during anoxia but recovered fully after a period of postanoxic oxygen‐ation. Low pH (6.2) suppressed K+ stimulation of acetylcholine release, and after a period of anoxia at low pH the recovery of acetylcholine release was only partial. With lactate plus pyruvate as substrate, the effects of anoxia and/or low pH on acetylcholine release and its subsequent recovery were exacerbated. Choline release from synaptosomes, however, was not affected by anoxic/ionic conditions in the same way as acetylcholine release. At low pH (6.2) there was a marked reduction in choline release both under aerobic and anoxic conditions. These results suggest that acetylcholine release per se from the nerve is very sensitive to anoxic insult and that the low pH occurring during anoxia may be an important contributory factor.
影响因子：
5.8
作者：
Gibson,GE;Peterson,C
通讯作者：
Peterson,C
3,4-二氨基吡啶在缺氧期间改变乙酰胆碱代谢和行为。
DOI：
--
发表时间：
1982
期刊：
The Journal of pharmacology and experimental therapeutics
影响因子：
--
作者：
Peterson,C;Gibson,GE
通讯作者：
Gibson,GE
体外隔膜和海马的乙酰胆碱和氧化代谢。
DOI：
--
发表时间：
1983
期刊：
The Journal of biological chemistry
影响因子：
--
作者：
Gibson,GE;Peterson,C
通讯作者：
Peterson,C