[Measurement of serum insulin-like growth factor-I by enzyme-linked immunosorbent assay in uremic patients and uninephrectomized patients].

Using the enzyme-linked immunosorbent assay (ELISA), we determined the serum insulin-like growth factor-I (IGF-I) levels in the patients on hemodialysis and patients who had undergone unilateral nephrectomy. This ELISA system was able to detect IGF-I over the range of 1.6 to 50 ng/ml. The serum IGF-I levels in 45 male and 34 female dialytic patients (12.7 +/- 7.4 ng/ml and 29.0 +/- 15.9 ng/ml) were significantly low (P < 0.01) compared with 50 normal adult men and 53 normal adult women (34.9 +/- 11.4 ng/ml and 44.5 +/- 20.5 ng/ml). The serum IGF-I level tended to decrease with aging. Furthermore, we determined the IGF-I levels in 5 donors for living-related kidney transplantation and 7 patients with upper urinary tract tumor before and after unilateral nephrectomy in order to examine the endocrine effect of IGF-I. The IGF-I level in the donors decreased significantly (P < 0.05) on the fifth postoperative day and returned to the preoperative level on the 14th postoperative day. The IGF-I level in the tumor patients decreased significantly on the fifth postoperative day (P < 0.01) and remained at a low level up to the 14th postoperative day. However, the changes in the postoperative IGF-I level in the patients who had undergone surgical operations other than unilateral nephrectomy showed patterns similar to those in the kidney transplantation donors. These findings suggest that the postoperative fall in the serum IGF-I is affected by either fasting after surgery or consumption due to healing of the operative wound.