[Stereoselectivity in absorption of trans tramadol in rat intestine].
OBJECTIVE
To investigate the stereoselectivity in absorption of trans tramadol (trans T) in rat intestine.


METHODS
The duodenum, jejunum and ileum were separately perfusated in situ with trans T dissolved in Krebs-Ringer buffer. Trans T enantiomers in the perfusate were analyzed with a high performance capillary electrophoresis (HPCE) method.


RESULTS
The absorbed fractions of trans T enantiomers were similar among the different segments of the rat intestine. The absorbed fraction of (+)-trans T was lower than that of (-)-trans T when the concentration of trans T was not higher than 40 mumol.L-1. As the concentration of trans T increased, the absorbed fractions of trans T enantiomers were reduced and the difference in absorbed fractions between trans T enantiomers became not significant.


CONCLUSIONS
Trans T enantiomers can be absorbed in different parts of the rat intestine. The intestinal absorption of trans T was stereoselective, (-)-trans T being preferentially absorbed.
Liu
Hui-chen
HC
Department of Clinical Pharmacology, Bethune International Peace Hospital, Department of Pharmacology, Hebei Medical University, Shijiazhuang, China.
Li
Bao-xin
BX
Dun
Bin
B
Wang
Yong-li
YL
D000701:Analgesics, Opioid / Q000493:pharmacokinetics; D000818:Animals; D004386:Duodenum / Q000378:metabolism; D005260:Female; D007082:Ileum / Q000378:metabolism; D007408:Intestinal Absorption; D007421:Intestine, Small / Q000378:metabolism*; D007583:Jejunum / Q000378:metabolism; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013237:Stereoisomerism; D014147:Tramadol / Q000493:pharmacokinetics*
D000701:Analgesics, Opioid; D014147:Tramadol