Growth hormone aggravates glomerular sclerosis in the remnant kidney of 5/6 nephrectomized uremic rats

Background Our study evaluated the influence of short-term growth hormone treatment on the remnant kidney in 5/6 nephrectomized uremic rats Methods Twenty male Sprague-Dawley rats were divided into 4 groups: sham-operated control rats (SC, n=4); sham-operated rats treated with recombinant human growth hormone (SGH, n=4); uremic (5/6 nephrectomized) control rats (UrC, n=6); and uremic rats treated with recombinant human growth hormone (UrGH, n=6). Total food intake, food efficiency, average daily food intake per 100 g body weight, weight gain, increase in body length, creatinine clearance, and kidney weight per 100 g body weight were measured. Glomerular tuft area was determined, and the severity of glomerular sclerosis was scored. Insulin-like growth factor-I was localized in the kidneys by immunostaining. Results Weight gain, increase in body length, food efficiency, and food intake per unit body weight were greatest in the SGH group; in UrGH animals, food efficiency and food intake per unit body weight were significantly higher than those in UrC rats. Creatinine clearance in uremic rats was significantly reduced compared with that in sham-operated animals. There was no difference in the ratio of kidney weight to body weight among the groups. The average glomerular area was greatest, and the glomerular sclerosis index was highest, in the UrGH group. No insulin-like growth factor-I could be identified in the glomeruli. Conclusions Growth-hormone treatment augmented daily food intake, and the more rapid progression to glomerular sclerosis in hormone-treated uremic rats is probably due mainly to increased daily protein intake. This study was partly presented at both the 38th Annual Meeting of the Japanese Society of Nephrology and the Sixth Asian Pacific Congress of Nephrology