Active transport of L-selenomethionine in the intestine

Publisher Website
Google Scholar
Abstract
It has been established that there is an active transport of L-seleno-75 methionine across the intestine of the hamster. The transport rate of L-seleno-75 methionine across the small intestine varies from segment to segment. Glucose (5.5 m[image]) and galactose (5.5 m[image]) inhibit the transport of L-seleno-75 methionine, 22 and 24%, respectively. Ouabain (10-6 [image]) reduces the transport of L-seleno-75 methionine only if present on the serosal side, but not on the mucosal side, indicating that the transport of L-seleno-75 methionine is dependent upon the sodium pump. Phlorizin (10-4 [image]) does not affect the transport of L-seleno-75 methionine but does reduce the inhibitory effect of hexoses. The mucosal-to-serosal flux of L-seleno-75 methionine apparently requires an aerobic pathway involving oxidative phosphorylation since 2,4-DNP (10-3 [image]) and KCN (10-3 [image]) reduce the transport of L-seleno-75 methionine 75 and 67%, respectively. DL-Selenomethionine (10 m[image]) can reduce the rate of active transport of C14 DL-methionine (1 m[image]), the corresponding S analogue, by 78% suggesting that selenomethionine and methionine utilize the same transport system. The implications of the S-Se antagonism in relation to active transport and selenium poisoning are discussed.