Murakami M, Seo Y, Watari H
Department of Molecular Physiology, National Institute for Physiological Sciences, Okazaki, Japan.
Am J Physiol. 1988 May;254(5 Pt 1):G781-7. doi: 10.1152/ajpgi.1988.254.5.G781.
The effects of a high dose of acetylcholine (ACh) on oxygen consumption (VO2) and changes in phosphorus energy metabolites during secretion were studied in isolated perfused mandibular gland of rats at 24 degrees C. Sugar phosphates (SP), Pi, phosphocreatine (PCr), and ATP were identified by phosphorus-31 nuclear magnetic resonance spectroscopy. One micromole ACh induced a tachyphylactic secretory response, a persistently elevated VO2, and decreased PCr and ATP; 1 mM ACh caused an initial burst of secretion that was followed by suppression of secretion and a rapid increase in the VO2 to the same level as that with 1 microM ACh. These findings indicate a dissociation between secretion and VO2. During stimulation with 1 mM ACh, the level of PCr first decreased and then partially recovered, but the level of ATP continued to decrease and the levels of Pi and SP increased markedly. These findings suggest compartmentalization of creatine phosphokinase (CPK) systems and the possibility that a high concentration of ACh interferes with the transport of PCr between one CPK system near adenosinetriphosphatase and another system near mitochondria in acinar cells.
在24℃下，对大鼠离体灌注下颌下腺进行研究，观察高剂量乙酰胆碱（ACh）对分泌过程中氧消耗（VO2）以及磷能量代谢物变化的影响。通过磷-31核磁共振波谱法鉴定糖磷酸盐（SP）、无机磷酸盐（Pi）、磷酸肌酸（PCr）和三磷酸腺苷（ATP）。1微摩尔ACh诱导速发性分泌反应、VO2持续升高以及PCr和ATP降低；1毫摩尔ACh引起初始分泌爆发，随后分泌受抑制，VO2迅速升高至与1微摩尔ACh时相同水平。这些发现表明分泌与VO2之间存在分离。在用1毫摩尔ACh刺激期间，PCr水平先降低然后部分恢复，但ATP水平持续降低，Pi和SP水平显著升高。这些发现提示肌酸磷酸激酶（CPK）系统存在区室化，以及高浓度ACh可能干扰腺泡细胞中靠近三磷酸腺苷酶的一个CPK系统与靠近线粒体的另一个系统之间PCr的转运。
