Teraoka H, Sugawara T, Nakazato Y
Department of Pharmacology, Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan.
J Neurochem. 1993 May;60(5):1936-40. doi: 10.1111/j.1471-4159.1993.tb13423.x.
Differential adrenaline (Ad) and noradrenaline (NA) secretions evoked by secretagogues were investigated using digitonin-permeabilized adrenal chromaffin cells, cultured adrenal chromaffin cells, and perfused adrenal glands of the ox. In digitonin-permeabilized cells, Ca2+ (0.8-160 microM) caused a concentration-dependent increase in catecholamine secretion, which was characterized by a predominance of NA over Ad secretion. Acetylcholine (10-1,000 microM), high K+ (14-56 mM), and bradykinin (0.1-1,000 nM) all were confirmed to induce the release of more NA than Ad at all concentrations used. There was no apparent difference in the ratios of NA/Ad between Ca(2+)-induced catecholamine secretion from digitonin-permeabilized cells and those induced by secretagogues from cultured cells. Qualitatively the same result was obtained in the secretory responses to acetylcholine and high K+ in perfused adrenal glands. These results indicate that the effectiveness of Ca2+ for catecholamine secretion is higher in the secretory apparatus of NA cells than in that of Ad cells of the bovine adrenal medulla. This may be one of the reasons why the secretagogues cause a predominance of NA secretion over Ad secretion in the bovine adrenal medulla.
利用洋地黄皂苷通透的肾上腺嗜铬细胞、培养的肾上腺嗜铬细胞以及牛的灌注肾上腺，研究了促分泌剂诱发的肾上腺素（Ad）和去甲肾上腺素（NA）分泌差异。在洋地黄皂苷通透的细胞中，Ca2+（0.8 - 160 microM）引起儿茶酚胺分泌呈浓度依赖性增加，其特征是NA分泌多于Ad分泌。乙酰胆碱（10 - 1000 microM）、高钾（14 - 56 mM）和缓激肽（0.1 - 1000 nM）在所有使用浓度下均被证实诱导释放的NA多于Ad。洋地黄皂苷通透细胞中Ca(2+)诱导的儿茶酚胺分泌与培养细胞中促分泌剂诱导的儿茶酚胺分泌的NA/Ad比值无明显差异。在灌注肾上腺中对乙酰胆碱和高钾的分泌反应中定性地获得了相同的结果。这些结果表明，Ca2+对儿茶酚胺分泌的有效性在牛肾上腺髓质的NA细胞分泌装置中高于Ad细胞。这可能是促分泌剂在牛肾上腺髓质中导致NA分泌多于Ad分泌的原因之一。
