Improved growth in growth retarded uremic rats with use of calorie supplementation.

: Renal failure in childhood is often associated with poor growth. Growth in uremia was studied using young growing male Sprague-Dawley rats made moderately uremic (SUN77 mg/100 ml) by partial nephrectomy. Uremic rats weighed less than control rats after 17 days of observation (P less than .01). Uremic rats supplemented by corn oil gavage had significantly better weight gain than nonsupplemented uremic rats (P less than .005). Uremic rats whose appetite was stimulated by the addition of saccharin to diet also had significantly better daily weight gain than uremic rats not having saccharin added to diet (P less than .05). Calorie intake appeared to be the limiting variable with regard to observed differences in growth. In fact, when adjusted for calorie intake/weight-75, uremic rats did not differ from control rats in weight gain/weight-75. In addition, control rats fed diets identical to those consumed by uremic rats grew equally as poorly. Improved growth in uremic rats with calorie supplementation was felt to be real growth in that body composition studies showed proportionate gains in cell mass, total body solids, liver and muscle. Catch-up growth was not observed, perhaps because insufficient supplemental calories were provided or because other unexplained factors contributed to growth retardation.