Ahnert-Hilger G, Wiedenmann B
Abt. Gastroenterologie, Freie Universität Berlin, Germany.
FEBS Lett. 1992 Dec 7;314(1):41-4. doi: 10.1016/0014-5793(92)81457-w.
Treatment of AR42J cells with dexamethasone leads to an enhanced formation of amylase-containing granules and facilitates their regulated secretion. Besides the exocrine properties, AR42J cells possess a specific uptake system for [3H]GABA. The stored GABA can be released upon potassium depolarisation in a Ca(2+)-dependent manner. After treatment with dexamethasone, potassium depolarisation fails to release GABA, but instead causes a Ca(2+)-dependent secretion of amylase. Since vesicles similar to small synaptic vesicles of neurons have been identified in AR42J cells, we suggest that the regulated GABA release is mediated by this vesicle type. It is tentatively speculated that other epithelial cells, which also contain small synaptic vesicles and amino acid neurotransmitters, may release them in a similar fashion.
用地塞米松处理AR42J细胞会导致含淀粉酶颗粒的形成增加，并促进其调节性分泌。除了外分泌特性外，AR42J细胞还具有针对[3H]GABA的特异性摄取系统。储存的GABA可在钾去极化时以Ca(2+)依赖的方式释放。用地塞米松处理后，钾去极化无法释放GABA，反而会导致淀粉酶的Ca(2+)依赖分泌。由于在AR42J细胞中已鉴定出与神经元小突触小泡相似的囊泡，我们认为调节性GABA释放是由这种囊泡类型介导的。初步推测，其他也含有小突触小泡和氨基酸神经递质的上皮细胞可能以类似方式释放它们。
