Résumé
Lactoferrin (Lf), an iron-binding multifunctional glycoprotein, abundantly present in colostrum and milk of different species such as humans, bovines, and mice has been shown that bovine colostral Lf is transported into the CSF via plasma in newborn calves. Specific Lf-receptors (Lf-R) are present in different cells of different species. In the present study, we report for the first time, the presence and distribution of Lf-R in the intestine and choroid plexus in newborn calves. Brush-border membrane vesicles (BBMV) were prepared from the mucosa of duodenum, jejunum, ileum, colon, epithelium overlying Peyer's patches (EOPP) in jejunum (EOPPJ) and ileum (EOPPI), and choroid plexus membranes. Receptor binding assays were carried out using 125I labeled bovine Lf. Specific and saturable Lf-R were found in BBMV of all the intestinal segments and choroid plexus examined. Nonlinear regression and Scatchard plot analyses clearly revealed that EOPP had the highest binding maximal (Bmax), and lowest in colon. The maximum dissociation constant (Kd) 0.7 microM was in colon while, Bmax and Kd in choroid plexus membrane were 16.87 nmol/mg protein and 0.34 microM, respectively. All these findings together strongly suggested that Lf was transported into CSF via plasma through receptor mediated transcytosis.
Sujets)
Animaux , Animaux nouveau-nés , Bovins , Plexus choroïde/métabolisme , Système digestif/métabolisme , Microvillosités/métabolisme , Liaison aux protéines , Récepteurs de surface cellulaire/métabolismeRésumé
Extract of Nelumbo nucifera rhizome (RNN) was used as anti-diarrheal agent to combat the diarrhea in experimental rats. The RNN extract in graded doses (100, 200, 400 and 600 mg/kg body wt.) reduced not only the frequency of defecation, wetness of fecal dropping and PGE2 induced enteropooling but also the propulsive movements of charcoal meal significantly.