The food intake, growth rate, and serum GH, somatomedin (SM), and SM carrier protein levels in young, partially nephrectomized rats with renal failure (RF) were compared with those of their nutritionally matched (NM) and ad libitum (AL) fed sham-operated controls over a period of 8 weeks to study the effects of renal impairment on growth and the growth-promoting system and to determine what contribution, if any, may be due to malnutrition. During the 8 weeks of study, the RF and NM animals consumed 19% less food than the AL controls, and their mean growth rates, measured as gain in body weight, were 57% and 25% less, respectively. While consuming the same amount of food, the growth retardation of RF rats was significantly greater (P < 0.05) than that of NM controls. A significant negative correlation coefficient (r = -0.845; P < 0.001) was found at the end of 4 weeks between body weight and the degree of renal impairment, expressed as elevated blood urea nitrogen (BUN), in RF rats. Although serum GH levels showed no consistent pattern of change in any of the groups of rats during the period of study, SM activity, expressed as insulin-like growth factor reactivity, demonstrated a significant (P < 0.001) positive correlation with body weight in all groups. In the RF group, serum IGF also exhibited a negative correlation with BUN (r = -0.518; P < 0.001). Serum carrier protein levels rose proportionately with body weight in the AL and NM controls, but not in the RF rats. Analysis of these results indicates that in each of the three groups of rats, the growth rate is age related and proportional to food intake, and significant correlations exist between body weight and serum insulin-like growth factor levels. Moreover, food intake, body weight, and serum IGF in RF rats are inversely proportional to the degree of renal impairment estimated by BUN levels. While malnutrition appears to be a major cause of the growth retardation observed in rats with renal impairment, the greater reduction in the growth rate of RF animals compared to their NM controls suggests that other, yet undefined factors associated with renal impairment also retard the process of growth in these animals. (Endocrinology108: 1683, 1981)
No takes yet. Share an insight, caveat, or question.
Schalch et al. (1981) studied this question.