Abstract
The kinetics of peritoneal transport of insulin-like growth factor (IGF) system-related proteins during dialysis is not well characterized. We studied temporal changes in dialysate and serum concentrations of IGF-I and IGF-II as well as IGF binding protein (BP)-1, -2, and -3 in ten children with end-stage renal disease (ESRD) undergoing continuous cycling peritoneal dialysis (CCPD) during a 4-h peritoneal equilibration test (PET). Dialysate concentrations of IGF-I, IGF-II, and all three IGFBPs demonstrated a time-dependent increase during PET. Despite their transport, the serum concentrations of these proteins did not change significantly during the PET. Dialysate/serum ratios for IGF-I, IGF-II, and IGFBP-1, -2, and -3 were significantly increased at 2 h and increased further at 4 h, at which time values averaged 1.3 ± 0.2%, 3.1 ± 0.5%, 6.2 ± 1.0%, 2.4 ± 0.2%, and 1.3 ± 0.2% of serum levels, respectively. The transperitoneal clearance (μl/min per 1.73 m2) of the three IGFBPs was inversely related to both their molecular weight and plasma concentration. However, peritoneal clearance of IGF-I and -II was similar to that of the larger and more-abundant IGFBP-3. Mass transfer rates (μg/h per 1.73 m2) for the IGFs and their binding proteins were directly proportional to their prevailing plasma concentration. Based on estimates of mass transfer, only a small molar excess of IGFBPs was removed from the circulation relative to the combined molar concentration of IGF-I and IGF-II. Hence, it seems unlikely that any beneficial effect of CCPD on growth in children with ESRD is mediated via a preferential loss of IGFBPs into the dialysate fluid.
Original language | English (US) |
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Pages (from-to) | 581-588 |
Number of pages | 8 |
Journal | Pediatric Nephrology |
Volume | 12 |
Issue number | 7 |
DOIs | |
State | Published - Sep 1998 |
Externally published | Yes |
Keywords
- Clearance
- Continuous cycling peritoneal dialysis
- End-stage renal failure
- Insulin-like growth factor binding proteins
- Insulin-like growth factors
- Mass transfer
- Peritoneal dialysate
- Peritoneal dialysis
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health
- Nephrology