Abstract: AIM: To explore the relationshiPbetween left ventricularhypertrophy (LVH) and endothelial function(EF) and to investigate the effects of L-Arginine and Vitamin C on LVH and EF in spontaneously hypertensive rats (SHR).METHODS: 20 SHrwith 8 weeks old were randomly divided into experiment grouP(12 rats)and treated grouP(8 rats) while 8 WKY rats were selected as a control group.The SHrof treated grouPreceived L-Arginine and Vitamin C (7.5 and 4-5 g·L^-1 respectively in drinking water) for12 weeks,but the WKY rats and the SHrof experiment grouPwere given distilled wateras drinking water.The rats with 20 weeks old were killed aftermeasurements of theirblood pressure and body weight.HE and VG staining combined with computed morphometry were employed to evaluate the cardiomyocyte diameter(CDM),the collagen volume fraction (CVF),perivascularcircumferential area (PCA) on the left ventriculartissue.RESULTS: Compared with the WKY,the blood pressure was higher,heart rate was faster,left ventricularmass (LVMI) were higher,NO was lowerin the experimental group.The CVF,PCA and CDM were higherin the experimental group.There were no differences in body weight between the experiment grouPand the control.Bivariate analysis showed that in the experiment grouPLVMI correlated well with NO,CVF,PCA orCDM (r=0.80,0.68,0.66,P<0.01).Besides,NOin the experiment grouPcorrelated well with CDM,CVF orPCA (r=-0.65,-0.54,-0.52,P<0.01 orP<0.05).Compared with the experiment group,LVMI,CDM,CVF,and PCA were lowerin the treated group.There was higherNO level in the treated group.There were no significant differences in blood pressure,body weight and heart rate.Compared with the control,blood pressure,heart rate,LVMI,CDM,CVF and PCA still increased.There were no significant difference in body weight and in NO between WKY and the treated group.CONCLUSIONS: LVH is related with endothelial dysfunction in SHR.The endothelial dysfunction may play a role in the development and progression of LVH by accelerating CDM and CVF and PCA increased.LL-Arginine and Vitamin C can hinderoff LVH to some degree by improving endothelial function.

Key words: spontaneously hypertensive, left ventricularypertrophy, endothelial function, L-arginine, vitamin C