Paracellular permeability of extracellular space markers across rat jejunum in vitro. Indication of a transepithelial fluid circuit.

Abstract

5. For all the markers used the e.c.s. estimates remained constant between the 40th and 80th min of incubation.6. In the absence of glucose the transepithelial net fluxes of each of the different markers were zero. In the presence of 28 mM glucose the serosato-mucosa fluxes of all markers were dramatically increased. The ratio between the serosa-to-rflucosa and the mucosa-to-serosa fluxes increased in the order [3H]7. The effect of glucose on the flux ratio of the marker substances suggests that glucose-induced net water transport to the serosa side of the gut wall represents the difference between a transcellular net water transport to the serosal side and a significant paracellular net water transport through the lateral intercellular spaces to the mucosal solution.

Lysine transport across rat jejunum: distribution between the transcellular and the paracellular routes.

“…From this application one would, in accordance with the data of Table 1 on J'Y" at 0 and 17 mM-glucose, expect an effect of glucose on lysine transport similar to its effect on mannitol transport (Table 3 and Munck & Rasmussen, 1977).…”

“…It has also been shown recently (Munck, 1976;Munck & Rasmussen, 1977) that with currently used in vitro techniques the relative importance of the paracellular route across rat jejunum is much increased when glucose is added to the incubation media. With the aim of evaluating the paracellular and transcellular components of lysine transport across the rat jejunum the present paper presents further information on these aspects of transepithelial permeability.…”

Acute effect of ethanol on intestinal calcium transport.

“…Since calcium can also be actively absorbed (3)(4)(5)(6) and secreted in the ileum (4,(6)(7)(8) and the effect of ethanol on ileal calcium transport in rats has not been studied, the present ex periments thus aimed to investigate the acute effects of intragastric administration of ethanol on net fluid and calcium absorption in vivo and by using an in situ intestinal loop technique to quantitate the calcium fluxes in the duodenum and ileum.…”

Fluid movements across rabbit ileum coupled to passive paracellular ion movements.

“…sucrose, inulin and polyethylene glycol (Wright, Smulders & Tormey, 1972;Berry & Boulpaep, 1975;Munck & Rasmussen, 1977; for review, see Ussing, Erlij & Lassen, 1974), which suggests that the permselectivity of the tight-junction is not based entirely on the size of the solute. There is considerable evidence to support the view that the tight-junction in loose epithelia are cationselective (Fromter, 1972;Fromter & Diamond, 1972;Frizzell & Schultz, 1972;Moreno & Diamond, 1975).…”