Adrenomedullin produced by glomerular epithelial cell inhibits mesangical cell proliferation

Purpose: To investigate the expression of adrenomedullin (AM) and its receptor calcitonin-receptor-like receptor (CRLR) on renal cells and the possible effect of AM on mesangial cell proliferation. Methods: RT-PCR was used to prepare the AM and CRLR probes, Northern blot used to detect the expression of AM and CRLR, [3H] thymidine incorporation used to measure cell proliferation. Results: AM was produced by glomerular epithelial cell (GEC), but not by mesangial cell (MsC), however, AM receptor CRLR was only expressed on MsC. GEC conditioned medium containing AM inhibited MsC growth and AM receptor blockade CGRP8-37 may partially decrease this inhibitory effect. Conclusions: It is suggested that AM as an important glomerular paracrine regulator is involved in glomerular integrity and inflamatory process.