Effects of maternal undernutrition on renal angiotensin II and chymase in hypertensive offspring.

Intrauterine growth restriction (IUGR) can program the future development of hypertension in adulthood. Renin-angiotensin system has been reported to play a role in the IUGR-induced hypertension. The aims of this study were to investigate the effects of IUGR on renal angiotensin-converting enzyme (ACE), angiotensin (Ang) II, and chymase expressions in IUGR-induced hypertension. Timed pregnant Sprague-Dawley rats received 50% rations of control food intakes from days 15 to 21 of gestation. Control rats received regular food throughout the pregnancies. We measured arterial blood pressures and glomerular number and performed immunohistochemical studies on kidney tissues in adult male offspring at 16 weeks of age. IUGR rats exhibited significantly lower body and kidney weight and reduced number of glomeruli when compared with control rats. IUGR rats had significantly higher systolic blood pressure than control rats. Immunoreactivity of ACE was comparable between control and IUGR rats while immunoreactivities of chymase and Ang II were significantly higher in IUGR rats than in control rats. In conclusion, immunohistochemical studies document up-regulation of ACE-independent Ang II and chymase in IUGR kidney and suggest that overactivity of chymase might result in increased intrarenal Ang II production, which may contribute to the development of hypertension in intrauterine undernourished rats.