Relationship Between The Plasma Levels Of Calcitonin Gene-Related Peptide And Diabetic Nephropathy

Objective To study the role of calcitonin gene-related peptide(CGRP), and the relationship between CGRP and endogenous creatinine clearance rate(Ccr) in the development of diabetic nephropathy, the plasma levels of CGRP and Ccr were measured in different stages of patients with diabetic nephropathy.Methods 75 patients with diabetic aellitus and 25 normal subjects were enrolled in the study, of wich 25 patients with type II diabetic mellitus(DM) without nephropathy were divided into DM group, 25 patients in clinical stage of diabetic nephropathy (DN) into DN group, 25 patients in renal failure stage of diabetic nephropathy(DNF) into DNF group and 25 normal subjects(NC) into control group. Radioimmunoassay was used to measure the plasma levels of CGRP. The experimental data were processed by analysis of variance , Dunnett test.Result Plasma levels of CGRP were 169.58pg/ml, 241.86pg/ml, 336. 57 pg/ml, 425.21pg/ml in NC, DM, DN and DNF group respectively. Plasma levels of CGRP increased with the severity of diabetic nephropathy. There were significant statistical differences between NC group and any study group, and between DM group and any other study group (P<0. 01). There was significantly negative correlation between CGRP and Ccr (r=-0.76, P<0.01).Conclusion 1. With the development of diabetic nephropathy, plasma level of CGRP increases significantly. 2. While Ccr drops, CGRP goes up compensatively, and 3. CGRP may contribute to relax the blood vessels of the body in order to resist the secondary hypertension and CGRP mayplay an important role in delaying the development of diabetic nephropathy.