Nakahari T, Nakamura A, Imai Y
Department of Physiology, Osaka Medical College, Takatsuki, Japan.
Jpn J Physiol. 1995;45(1):23-36. doi: 10.2170/jjphysiol.45.23.
Exocytosis in the perfused rat submandibular gland was studied using electron microscopy. Stimulation with 1 microM acetylcholine (ACh) evoked exocytosis; i.e., the secretory granules fused with the luminal membrane and their contents were extruded into the luminal space, and watery vacuoles were observed in some acinar cells. Stimulation with 1 mM ACh also induced exocytosis, and led to a marked increase in the number of watery vacuoles. Some watery vacuoles were connected to the lumen and were thus suggested to be formed by the fusion of the granules. On the other hand, no watery vacuoles were observed in the acinar cells during 1 microM isoproterenol stimulation, while isoproterenol induced exocytosis and led to a marked decrease in the number of intracellular granules. Thus, the watery vacuolation is a characteristic response to the cholinergic stimulation, is dependent on the ACh dose in the submandibular acinar cells, and is regarded as a kind of exocytosis.
利用电子显微镜研究了灌注大鼠下颌下腺中的胞吐作用。用1微摩尔乙酰胆碱（ACh）刺激可诱发胞吐作用；即分泌颗粒与管腔膜融合，其内容物被挤出到管腔空间，并且在一些腺泡细胞中观察到水样空泡。用1毫摩尔ACh刺激也诱导胞吐作用，并导致水样空泡数量显著增加。一些水样空泡与管腔相连，因此提示是由颗粒融合形成的。另一方面，在1微摩尔异丙肾上腺素刺激期间，腺泡细胞中未观察到水样空泡，而异丙肾上腺素诱导胞吐作用并导致细胞内颗粒数量显著减少。因此，水样空泡化是对胆碱能刺激的一种特征性反应，取决于下颌下腺泡细胞中的ACh剂量，并且被视为一种胞吐作用。
