D-Glucose absorption, distinguishing between active and diffusive components, has been studied in the ileum of spontaneously hypertensive rats (SHR) and their normotensive control, Wistar-Kyoto (WKY) rats, using a perfusion system in vivo (Vinardell & Bolufer, 1983). In addition, net water transport has also been determined. Twelve-week-old rats were fasted for 18 h and anaesthetised with urethane (1.25 g (kg body weight)^-1) before performing a laparotomy; they were humanely killed at the end of the experiment. A significant decrease in total D-glucose absorption was found in SHR when compared to WKY rats, this reduction being due to a lower SGLT1-mediated component. This effect was not compensated by the total diffusive component, since the phlorizin-insensitive D-glucose absorption did not significantly change between the two rat strains. However, the diffusive component of D-glucose transport was relatively more important in hypertensive than in normotensive rats. The use of 2,4,6-triaminopyrimidine (TAP), which blocks the transport across the paracellular route, showed that the paracellular diffusion of D-glucose was higher in SHR than in WKY rats. On the other hand, intestinal net water transport was not modified between the two groups of animals, though the presence of phlorizin in the perfusate decreased the ileal water absorption to a greater extent in normotensive rats. Moreover, the addition of TAP produced a higher inhibition on the net water transport in WKY than in SHR, thus indicating that the transcellular transport of water is higher in hypertensive rats. In conclusion, the observed reduction in D-glucose absorption in vivo in the ileum of SHR was due to a decrease in the active, SGLT1-mediated component. The total D-glucose diffusive component did not compensate for this effect, although the paracellular diffusion of D-glucose was quantitatively higher in hypertensive than in normotensive rats.

Vinardell MP & Bolufer J (1983). J Physiol Biochem 39, 193-196.

This work was supported by grants from Ministerio de Sanidad, Fondo de Investigaciones Sanitarias (FIS 97/1143 and 99/1142). L. Gómez-Amores was supported by a grant from Sigma-Tau Laboratory.