Effects of distention and neostigmine on jejunal vascular resistance, oxygen uptake, and intraluminal pressure changes in ponies.
The influence of distention (high baseline intraluminal pressure) and neostigmine methylsulfate on intestinal vascular resistance, oxygen uptake, and intraluminal pressure changes (rhythmic contractions) was studied in terminal jejunal segments, which were perfused at a constant rate, in 16 anesthetized ponies. When baseline intraluminal pressure was increased to 10 mm of Hg, the intestinal vascular resistance and amplitude of rhythmic contractions were increased. Neostigmine induced cyclic increases in amplitude of rhythmic contractions whether intraluminal pressure was 0 or 10 mm of Hg. Neostigmine also increased intestinal oxygen uptake at intraluminal pressures of 0 mm of Hg, but not at 10 mm of Hg, and vascular resistance was not altered at either intraluminal pressure. The results indicate that intestinal hemodynamics are adversely affected by distention. Further, neostigmine did not adversely affect intestinal hemodynamics while increasing rhythmic contractions, suggesting that neostigmine may be useful in the treatment of ileus in equids.
Parks
A H
AH
Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing 48824-1101.
Stick
J A
JA
Arden
W A
WA
Chou
C C
CC
Hengemuhle
S M
SM
D000818:Animals; D006736:Horses / Q000502:physiology*; D007583:Jejunum / Q000098:blood supply / Q000187:drug effects / Q000502:physiology*; D009119:Muscle Contraction / Q000187:drug effects; D009388:Neostigmine / Q000494:pharmacology*; D010101:Oxygen Consumption / Q000187:drug effects; D011312:Pressure; D014655:Vascular Resistance / Q000187:drug effects
D009388:Neostigmine