Effect of Low Birth Weight on Impaired Renal Development and Function and Hypertension in Rat Model

Abstract

Background/aim: Epidemiological studies have shown that low birth weight (LBW) is associated with a higher incidence of hypertension in adulthood. LBW may affect the kidney development, which in turn leads to impaired renal function and hypertension. Methods: Sprague-Dawley rats were fed isocaloric diets containing either 21% (w/w) (control group) or 10% (w/w) (LBW group) protein throughout pregnancy and chow during lactation. Renal function and structure of the offspring were measured from birth to 3 months. Results: At 3 weeks and 2 months, there was no difference in the volume of 24 h urine protein between the two groups. However, the volume was higher (117.17 ± 10.40 vs. 79.28 ± 14.26, p < 0.01) in LBW group at 3 months. Maternal protein intake did not alter serum creatinine in this study, but urine creatinine was lower in LBW group at 2 and 3 months. The creatinine clearance rate (Ccr) was significantly lower in LBW group than in control group at all time points. Glomerular number was reduced significantly in LBW group (22,720 ± 639 vs. 28,520 ± 526, p < 0.01) at 2 months, which was accompanied by an increase in blood pressure. There was a statistically significant negative correlation between the blood pressure and the glomerular number at 2 months (r = −0.919, p = 0.008). Conclusions: These data showed that abnormal kidney development and renal dysfunction occurred in LBW rats due to a maternal low-protein diet. Possessing a decreased glomerular number might be a risk factor for hypertension in LBW rats.

• low birth weight
• rats
• renal function
• blood pressure
• glomerular number

ACKNOWLEDGMENT

This work was supported in part by the Metabolic Syndrome Research Center of Central South University (Grant no. DY-2008-02-01).

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.