经典与非经典靶组织中两类1,25 - 二羟基维生素D3结合位点的证据。

Evidence for two classes of 1,25-dihydroxyvitamin D3 binding sites in classical vs. nonclassical target tissues.

作者信息

Gensure R C, Riggle P C, Antrobus S D, Walters M R

机构信息

Department of Physiology, Tulane University School of Medicine, New Orleans, LA 70112.

出版信息

Biochem Biophys Res Commun. 1991 Oct 31;180(2):867-73. doi: 10.1016/s0006-291x(05)81145-3.

DOI:10.1016/s0006-291x(05)81145-3

PMID:1659405

Abstract

Possible differences in 1,25-Dihydroxyvitamin D3 [1,25(OH)2D3] binding sites in classical and nonclassical target tissues were tested by Scatchard analysis of [3H]1,25(OH)2D3 binding in parallel chromatin preparations of rat kidney vs. testis. Two distinct binding components were resolved in kidney (p less than 0.005). Moreover, the single binding site in testis exhibited a 10-fold lower Kd (p less than 0.05) than did the principal binding site in kidney (50 +/- 4 vs. 405 +/- 142 pM). Secondly, regulation of [3H]1,25(OH)2D3 binding sites also differed. 1,25(OH)2D3 injection resulted in increased 1,25(OH)2D3 binding (p less than 0.05) in kidney (92%) and intestine (415%), but not in testis, lung or heart. These results suggest that the principal 1,25(OH)2D3 binding sites in classical targets kidney and intestine may be intrinsically different from those in at least some nonclassical targets.

摘要

通过对大鼠肾脏与睾丸平行染色质制剂中[3H]1,25(OH)2D3结合进行Scatchard分析，检测经典和非经典靶组织中1,25-二羟基维生素D3[1,25(OH)2D3]结合位点的可能差异。在肾脏中分辨出两个不同的结合成分（p<0.005）。此外，睾丸中的单一结合位点的解离常数（Kd）比肾脏中的主要结合位点低10倍（p<0.05）（50±4对405±142pM）。其次，[3H]1,25(OH)2D3结合位点的调节也有所不同。注射1,25(OH)2D3导致肾脏（92%）和肠道（415%）中1,25(OH)2D3结合增加（p<0.05），但在睾丸、肺或心脏中未增加。这些结果表明，经典靶组织肾脏和肠道中的主要1,25(OH)2D3结合位点可能与至少一些非经典靶组织中的结合位点本质上不同。