Further investigations on the transport mechanism of cephalexin and ampicillin across rat jejunum.
The transport mechanisms of cephalexin (CEX) and ampicillin (AB-PC) across rat jejunum were examined using the electrophysiological technique in vitro. From the experiments under the short-circuit condition, it became evident that the specific transport system participates in the mucosal-to-serosal transport of CEX, while AB-PC is transport only by the simple diffusion. In addition, the transport routes of these drugs were examined using the voltage-clamp technique. Salicylate, a model drug of the weak electrolyte, was transported mainly via a paracellular route, while CEX, in the absence of Na, penetrated the membrane via two routes, i.e. the transcellular route and the paracellular route. Similar result was obtained as to AB-PC. So it seems to be likely that these two drugs diffuse through the intestinal epithelium via the similar pathways in the Na-free condition.
D000667:Ampicillin / Q000378:metabolism*; D000818:Animals; D001692:Biological Transport; D002506:Cephalexin / Q000378:metabolism*; D066298:In Vitro Techniques; D007408:Intestinal Absorption; D007583:Jejunum / Q000378:metabolism; D008297:Male; D008564:Membrane Potentials; D051381:Rats; D011919:Rats, Inbred Strains; D012964:Sodium / Q000502:physiology
D000667:Ampicillin; D012964:Sodium; D002506:Cephalexin