** Prenatal alcohol exposure in the rat inhibits branching morphogenesis and causes a reduction in nephron endowment
Purpose: This study examined the effects of alcohol (ethanol) on the developing kidney using in vitro and in vivo techniques.
Methods: In vitro- metanephroi from day 13.5 embryos were grown in media containing 0, 0.5, 1 or 2% ethanol for 4 days then stained using a monoclonal anti-pan cytokeratin antibody and branch points and terminal tips counted. .
In vivo –Pregnant dams received a liquid diet containing no alcohol (controls) or a liquid diet containing 6% (v/v) ethanol throughout pregnancy. Dams littered down and kidneys collected at postnatal day (PN) 30 for determination of nephron number. Some animals were kept until 5 months of age for measurement of blood pressure.
Results: In vitro- Ethanol reduced branch points and terminal tips at all concentrations studied (P<0.05, one way ANOVA, table). Values are mean ± sem.
Control 0.5% 1% 2%
Branch points 22±3 15±2 16±3 14±2
Terminal tips 24±3 16±2 17±3 15±2
In vivo –Alcohol exposure did not affect birth weight or litter size. At PN30, total nephron number was reduced in alcohol exposed offspring (20,001±2469 versus 25,187±1463 in controls). At 5 months, systolic blood pressure was elevated in the alcohol exposed group (130±3 mmHg versus 119±2 mmHg in controls).
Conclusions: Ethanol exposure inhibits renal branching morphogenesis in vitro and results in a reduced nephron number and elevated blood pressure in male offspring. These results demonstrate a previously unknown effect of prenatal alcohol exposure on renal development which may contribute to the development of disease in later life.