کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
2531091 1558903 2016 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Inhibition of voltage-gated potassium channels mediates uncarboxylated osteocalcin-regulated insulin secretion in rat pancreatic β cells
ترجمه فارسی عنوان
مهار کانال های پتاسیم ولتاژ با استفاده از ترشح انسولین تنظیم شده توسط استئوکالسین غیر قلبی، در سلول های پانکراس موش صحرایی
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب سلولی و مولکولی
چکیده انگلیسی

Insulin secretion from pancreatic β cells is important to maintain glucose homeostasis and is regulated by electrical activities. Uncarboxylated osteocalcin, a bone-derived protein, has been reported to regulate glucose metabolism by increasing insulin secretion, stimulating β cell proliferation and improving insulin sensitivity. But the underlying mechanisms of uncarboxylated osteocalcin-modulated insulin secretion remain unclear. In the present study, we investigated the relationship of uncarboxylated osteocalcin-regulated insulin secretion and voltage-gated potassium (KV) channels, voltage-gated calcium channels in rat β cells. Insulin secretion was measured by radioimmunoassay. Channel currents and membrane action potentials were recorded using the conventional whole-cell patch-clamp technique. Calcium imaging system was used to analyze intracellular Ca2+ concentration ([Ca2+]i). The data show that under 16.7 mmol/l glucose conditions uncarboxylated osteocalcin alone increased insulin secretion and [Ca2+]i, but with no such effects on insulin secretion and [Ca2+]i in the presence of a KV channel blocker, tetraethylammonium chloride. In the patch-clamp experiments, uncarboxylated osteocalcin lengthened action potential duration and significantly inhibited KV currents, but had no influence on the characteristics of voltage-gated calcium channels. These results indicate that KV channels are involved in uncarboxylated osteocalcin-regulated insulin secretion in rat pancreatic β cells. By inhibiting KV channels, uncarboxylated osteocalcin prolongs action potential duration, increases intracellular Ca2+ concentration and finally promotes insulin secretion. This finding provides new insight into the mechanisms of osteocalcin-modulated insulin secretion.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: European Journal of Pharmacology - Volume 777, 15 April 2016, Pages 41–48
نویسندگان
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