NH4+ secretion in the avian colon. An actively regulated barrier to ammonium permeation of the colon mucosa.

Experiments were designed to characterize an active, electrogenic transport of NH(4)(+) ions across the colonic epithelium of the domestic fowl (Gallus gallus). Colonic segments were isolated and stripped of underlying muscle. The mucosal epithelia were mounted in Ussing chambers and voltage-clamped to measure the short-circuit currents (I(SC)) associated with transport.

Insight into the mechanism of short chain fatty acid absorption in the ostrich (Struthio camelus) proximal colon.

1. Occurrence of short chain fatty acids (SCFA) in anionic form limits their diffusion across the absorptive membrane. The present study sought to establish the mechanism of SCFA absorption in the ostrich.

Water absorption in relation to fermentation in the colon of the ostrich (Struthio camelus).

The colon is a major site for fermentation and water absorption in the ostrich. Water absorption along the colon was evaluated and its relationship to osmolality, Na+ concentration, short chain fatty acid (SCFA) concentration and carbohydrate content of digesta analysed. Mean water content decreased from 5.

Human rectal absorption of short- and medium-chain C2-C10 fatty acids.

Background: Current knowledge on the colonorectal absorption of medium-chain fatty acids is limited. The purpose of the present study was to evaluate and compare the human rectal absorption of short- and medium-chain C2-C10 fatty acids in healthy volunteers.

Methods: Dialysis bags containing 20 mmol x l(-1) of the fatty acids acetate, butyrate, hexanoate, octanoate, or decanoate in a phosphate-buffered (pH neutral) isoosmotic electrolyte solution were placed in the rectum for 30 min in 14 healthy volunteers.

Birth and prematurity influence intestinal function in the newborn pig.

Developmental changes in intestinal function occur in the perinatal period of many species. We investigated the hypothesis that gestational age at delivery and the mode of delivery influence intestinal function. Newborn pigs (106-108 or 113-115 days gestation, term = 115 +/- 2 days) were either delivered by caesarean section or born vaginally following induction of parturition with a prostaglandin F2 alpha analogue.