Surfeit calories during parenteral nutrition influences food intake and carcass adiposity in rats.

The relationship between surfeit caloric consumption during intravenous infusion of a parenteral nutrition solution providing 100% daily caloric needs (PN-100; glucose:fat:amino acid = 50:30:20), carcass adiposity, and postinfusion food intake was evaluated. Rats received saline (control) or PN-100 for 4 days via jugular vein. PN-100 rats were either allowed or denied access to chow during the infusion period. When food was available during the 4 days of PN-100, total cumulative caloric intake, eaten and infused, was 40% higher than controls (p < 0.01). Percent carcass adiposity was increased from 8.8% to 11.6% (p = 0.04), and there was a 3-day delay before food intake returned to baseline. When caloric intake was limited to that provided by PN-100, carcass adiposity was not increased and food intake was 86% of baseline during the first 24 h after stopping PN-100. Delayed return of normal food intake following PN-100 is the likely consequence of excess caloric ingestion during the PN-100 infusion period. The surfeit caloric intake resulted in increased carcass adiposity.