Efecto del ayuno sobre la absorción de L-glucosa en Passer domesticus

JUAN GABRIEL CHEDIACK; ANDRADA, M. E.; CAVIEDES-VIDAL, E.

San Luis

Congreso; XVII Reunión Científica Anual de la Sociedad de Biología de Cuyo.; 1999

Sociedad de Biología de Cuyo

Effect of fasting on passive absorption of L-glucose in house sparrows (Passer domesticus). Chediack J.G., Andrada M.E. y Caviedes-Vidal E. Unidad de Investigaciones en Cs Biol. U.N.S.L. E-mail:jchedi@unsl.edu.ar Introduction: Intestinal absorption of hydrophilic solutes occur mainly by passive diffusion. There are some evidences about a dynamic regulation of this pathway, for instance by compounds  such as sodium capriate and theophylline. However, is still unclear the modulation under several physiological stages, e.g. during fasting. To study this problem we use a intestinal marker L-glucose, a esteroisomer that not interact with glucose transporter, and is absorbed passively. Methods: Seven Passer domesticus were aclimated to laboratory conditions with water and food ad libitum. L-glucose solutions of 1 M were gavaged into the stomach with a syringe in three conditions: non fast, 2hr fasting and 12 hr fasting. Blood samples were extracted between 0 to 100 min after gavage, from a wing vein. The L-glucose was measured indirectly in plasma as the difference between total soluble carbohydrates (chemical  method), and D-glucose (enzimatic method). Results: The values of fractional absorption sugar (F) were F non fast = 46.32 ± 2.08 %, F2hs fasting = 43.29 ± 2.55 %, F12hs fasting = 44.08 ± 3.64 % and we did not find significative differences by ANOVA ( P = 0.716). Discussion: We concluded that intestinal passive absorption is  not dependent of solute concentration in the intestinal lumen, at least in birds. This work was support by UNSL grant N° 9502 and FONCYT 01-3101 to EC-V.