莫能菌素诱导培养的牛肾上腺髓质细胞和分离的嗜铬颗粒中22Na的内流及儿茶酚胺的释放。

Monensin-induced influx of 22Na and the release of catecholamines in cultured bovine adrenal medulla cells and isolated chromaffin granules.

作者信息

Izumi F, Wada A, Yanagihara N, Kobayashi H, Toyohira Y

出版信息

Biochem Pharmacol. 1986 Sep 1;35(17):2937-40. doi: 10.1016/0006-2952(86)90489-2.

Abstract

In cultured bovine adrenal medulla cells, monensin caused the release of catecholamines simultaneous with the influx of 22Na to the cells. The release of catecholamines by monensin was dependent on Na but not on Ca in the medium. Release of catecholamines and the influx of 22Na caused by monensin were not inhibited by tetrodotoxin. Monensin did not cause the release of dopamine beta-hydroxylase from the cells showing that monensin caused the release of catecholamines by a nonexocytotic mechanism. Similarly, in isolated chromaffin granules, monensin caused Na-dependent release of catecholamines, simultaneously with the influx of 22Na to the granules. Basing on these findings, monensin seems to cause a nonexocytotic release of catecholamines by acting as an Na ionophore both at cell membranes and chromaffin granule.

摘要

在培养的牛肾上腺髓质细胞中，莫能菌素导致儿茶酚胺释放，同时伴有22Na流入细胞。莫能菌素引起的儿茶酚胺释放依赖于培养基中的Na，而不依赖于Ca。莫能菌素引起的儿茶酚胺释放和22Na流入不受河豚毒素抑制。莫能菌素不会导致细胞释放多巴胺β-羟化酶，这表明莫能菌素通过非胞吐机制引起儿茶酚胺释放。同样，在分离的嗜铬颗粒中，莫能菌素导致儿茶酚胺的Na依赖性释放，同时伴有22Na流入颗粒。基于这些发现，莫能菌素似乎通过在细胞膜和嗜铬颗粒上作为Na离子载体来引起儿茶酚胺的非胞吐释放。