CHANGES IN STRUCTURAL AND FUNCTIONAL-PROPERTIES OF RAT INTESTINAL BRUSH-BORDER MEMBRANE DURING STARVATION

Changes in surface area of microvilli, fluidity of brush border membra ne and transport of L-amino acids through intestinal epithelial cells were studied in wellfed and starved (2,4 and 6 days) rats. The surface area of microvilli per unit area of intestinal epithelial cells incre ased during starvation. Studies with fluoroprobes - pyrene, 1-anilinon aphthalene-8-sulphonate and 1,6-diphenyl-1,3,5-hexatriene, showed incr eased fluidity of brush border membrane on progressive starvation. Tra nsport of five amino acids representing five different transport syste ms was studied during starvation in everted intestinal sleeves. Transp ort of L-proline, glycine and L-glutamic acid which represent imino, g lycine and acidic systems respectively increased significantly in Na+- dependent pathway whereas transport of L-lysine representing basic sys tem increased significantly in Na+-independent pathway during starvati on.