title: The comparative effects of abrupt vs. stepwise discontinuation of TPN in rats.
abstract: The comparative effects of discontinuing total parenteral nutrition (TPN: caloric ratio of glucose:fat:amino acid = 50:30:20) abruptly or in a stepwise manner on spontaneous food intake were investigated in two studies. Study 1: In 16 rats, TPN was given for 4 days, then stopped abruptly in eight rats. In the other eight rats, TPN was tapered; they received TPN at 75%, 50%, and 25% of their mean daily energy requirements per day for 3 consecutive days, and then switched to normal saline. Total parenteral nutrition induced a significant 60% reduction in spontaneous food intake (SFI) in both groups during the first TPN day. After 4 days of TPN, an 80% decrease in SFI had occurred in both groups. Resumption of SFI was significantly sooner in the abruptly-stopping group than in the stepwise-stopping group. But, in the latter group, there was a significantly greater cumulative caloric intake during the entire study. Study 2: In 32 rats, TPN providing either 100%, 50%, or 25% of their mean daily caloric requirements was given to three groups each of eight rats, for 3 days, then abruptly changed to normal saline; control rats received normal saline throughout. The TPN-induced decrease in SFI was proportional to the caloric density of the solution infused. Three days of 100%, 50%, or 25% TPN infusion led to an approximate 85%, 60%, or 35% decrease in SFI, respectively. Spontaneous food intake recovery was independent of the caloric density of TPN.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Surgery, University Hospital, SUNY Health Science Center, Syracuse 13210.
authors.forename: G
authors.initials: G
authors.lastname: Bodoky
authors.forename: A C
authors.initials: AC
authors.lastname: Campos
authors.forename: Z J
authors.initials: ZJ
authors.lastname: Yang
authors.forename: D C
authors.initials: DC
authors.lastname: Hitch
authors.forename: M M
authors.initials: MM
authors.lastname: Meguid
mesh_terms: D000818:Animals; D001835:Body Weight; D002149:Energy Intake / Q000502:physiology; D004734:Energy Metabolism / Q000502:physiology; D008297:Male; D010289:Parenteral Nutrition, Total; D051381:Rats; D011916:Rats, Inbred F344