Nephron number and blood pressure in rat offspring with maternal high-protein diet

Abstract.

This study investigated the effects of a high-protein diet during pregnancy on nephron endowment and subsequent levels of blood pressure in the offspring. Female WKY rats were fed either a normal (20%, NPD) or a high (54%, HPD) protein diet during pregnancy. Male offspring were paired at birth. At 4 weeks of age, 1 of the pair was randomly chosen for perfusion fixation, and total glomerular number, and thereby nephron number, was estimated using an unbiased stereological technique. The other rat of the pair was allowed to grow to 30 weeks of age, during which time tail cuff systolic blood pressure was monitored twice weekly. There was no effect of the HPD on birth weight (NPD 4.23±0.53 g, HPD 4.26±0.45 g, mean±SD), kidney weight (NPD 0.372±0.049 g, HPD 0.337±0.090 g), or total nephron number (NPD 27,191±3,512, HPD 26,738±4,735). Systolic blood pressure at 30 weeks was 170±14 mmHg in NPD and 169±14 in HPD offspring. These findings show that a HPD during pregnancy did not lead to an increase in birth weight, kidney weight, or nephron endowment, nor did the HPD affect adult blood pressure.