1. ¹Department of Internal Medicine, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
2. ²Department of Pediatrics- Neonatology, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
3. ³Department of Clinical Genetics, Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands
4. ⁴Department of Epidemiology and Department of Biostatistics Erasmus MC, University Medical Center Rotterdam, Rotterdam, The Netherlands

Correspondence: HL Tjiong, Department of Medicine, Erasmus MC's, Gravendijkwal 230, 3015 CE Rotterdam, The Netherlands. E-mail: h.tjiong@erasmusmc.nl

Received 19 February 2007; Revised 12 April 2007; Accepted 26 April 2007; Published online 6 June 2007.

Abstract

Patients with peritoneal dialysis are at risk for malnutrition and hypoalbuminemia, which are indicators of poor outcome. Recently, it was shown that dialysis solutions containing amino acids (AAs) and glucose improve protein anabolism in peritoneal dialysis patients. We determined if the same solutions could increase the fractional synthesis rate of albumin along with whole-body protein synthesis. Changes in the fractional albumin synthetic rate reflect acute change in hepatic albumin synthesis. A random-order cross-over study compared the effects of Nutrineal^® (AA source) plus Physioneal^® (glucose) dialysate with Physioneal^® alone dialysate. Eight patients in the overnight fasting state were compared to 12 patients in the daytime-fed state. Fractional albumin synthetic rate and whole-body protein synthesis were determined simultaneously using a primed-continuous infusion of L-[1-¹³C]-leucine. Fractional albumin synthesis on AAs plus glucose dialysis did not differ significantly from that on glucose alone in the fasting or the fed state. Protein intake by itself (fed versus fasting) failed to induce a significant increase in the fractional synthetic rate of albumin. Conversely, the oral protein brought about a significant stimulation of whole-body protein synthesis. Our findings show that the supply of AAs has different effects on whole-body protein synthesis and the fractional synthetic rate of albumin.