Yule D I, Lawrie A M, Gallacher D V
MRC Secretory Control Research Group, University of Liverpool, UK.
Cell Calcium. 1991 Feb-Mar;12(2-3):145-51. doi: 10.1016/0143-4160(91)90016-8.
Receptor-activated cytoplasmic calcium (Ca2+) oscillations have been investigated in single pancreatic acinar cells by microfluorimetry (Fura-2 as indicator). At submaximal concentrations of the agonists acetylcholine (ACh) and cholecystokinin octapeptide (CCK-8), both give rise to oscillatory changes in the cytosolic free calcium concentration ([Ca2+]i). The patterns of oscillations are markedly and consistently different for each of these two agonists. The ACh induced oscillations are superimposed upon a median elevation in background [Ca2+]i. The CCK-8 induced oscillations are of longer duration with [Ca2+]i returning to prestimulus levels between the discrete spikes. The ACh induced oscillations are rapidly abolished upon removal of extracellular Ca2+ while the CCK-8 induced oscillations persist for many minutes in the absence of external Ca2+. The CCK-8, but not the ACh, induced oscillations are increased in duration by the protein kinase C (PKC) inhibitor staurosporine and abolished by the PKC activating phorbol ester PMA. It is clear that CCK-8 and ACh do not activate receptor transduction mechanisms in an identical manner to generate oscillating [Ca2+]i signals.
已通过微量荧光测定法（以Fura-2为指示剂）在单个胰腺腺泡细胞中研究了受体激活的细胞质钙（Ca2+）振荡。在激动剂乙酰胆碱（ACh）和八肽胆囊收缩素（CCK-8）的亚最大浓度下，两者都会引起细胞质游离钙浓度（[Ca2+]i）的振荡变化。这两种激动剂各自引起的振荡模式明显且始终不同。ACh诱导的振荡叠加在背景[Ca2+]i的中度升高之上。CCK-8诱导的振荡持续时间更长，在离散的尖峰之间[Ca2+]i恢复到刺激前水平。去除细胞外Ca2+后，ACh诱导的振荡迅速消失，而在没有外部Ca2+的情况下，CCK-8诱导的振荡持续许多分钟。蛋白激酶C（PKC）抑制剂星形孢菌素可延长CCK-8而非ACh诱导的振荡持续时间，而PKC激活剂佛波酯PMA可消除该振荡。显然，CCK-8和ACh激活受体转导机制的方式并不相同，无法产生振荡的[Ca2+]i信号。
