The Change of Expression of Nitric Oxide Synthase (NOS) Isoforms on the Contralateral Kidney after Renal Infarction in Rat

Kim, Jeong Min; Song, Ki Hak; Kim, Kwang Jin

Abstract

PURPOSE: Nitric oxide (NO) is known as the free radical which acts on the relaxation of the vascular smooth muscle. We performed the artificial renal infarction on the ipsilateral renal artery, and investigated the change of expressions of nitric oxide synthase (NOS) isoforms on the contralateral kindey of the rats.
MATERIALS AND METHODS
Spraque-Dawley rats (300-350gm) were divided into 2 groups as control group (n=10) and operation group (n=30). Control group was performed sham operation and operation group was ligated the left renal artery with 5-0 silk. At the 1 week after operation, right kidney was obtained and determined expression of nNOS, eNOS and iNOS using immunohistochemical staining and the intensities of expression of NOS isoforms were analyzed with image analyzer. We also checked the blood pressure by tail-cuff method before and 1 week after operation.
RESULTS
Average systolic BP was elevated on the operation group significantly. While in the control group, which was 128.7 +/- 1.5mmHg initially, to 127.2 +/- 3.3mmHg 1 week later, in the operation group 123.8 +/- 3.2mmHg to 152.5 +/- 4.3mmHg. The intensities of NOS isoform, only the nNOS in the glomerular area was increased with significance statistically, but eNOS and iNOS were not increased. In tubular area, there were no evidences of increment of the intensities.
CONCLUSIONS
These results suggested that when the renal infarction was developed, nNOS which located in the renal glomerular area may has relations with influence on the renal blood flow and renin-angiotensin aldosterone on contralateral kidney. We were convinced that nNOS play a important role of the integral modulator of renovascular message system which result in the renovascular hypertension after all.