title: Mutagenicity of enantiomers of penbutolol.
abstract: With a view to examine the effect of chirality and the cause of batch-to-batch variation in the mutagenicity of penbutolol, penbutolol enantiomers - isopenbutolol [R(+)-enantiomer] and penbutolol [S(-)-enantiomer] - and two batches of Betapressin were tested employing the Ames Salmonella tester strain TA98. The mutagenic activity of R(+)-enantiomer was found to be similar to that of a batch of penbutolol with a high content of this optical isomer. The pharmaceutical form of penbutolol, Betapressin, exhibited either less or equal mutagenic effectiveness to the S(-)-enantiomer. In the presence of the S9 mix, the mutagenicity of R(+)-enantiomer was only slightly affected in the low dose range of 40 to 160 micrograms/plate. A metabolite of penbutolol, (RS) l"-dehydropenbutolol, did not cause an increase in the number of revertants/plate.
authors.affiliation: Department of Biological and Medical Research, King Faisal Specialist Hospital and Research Centre, Riyadh, Saudi Arabia.
authors.forename: S S
authors.initials: SS
authors.lastname: Hussain
authors.forename: H Y
authors.initials: HY
authors.lastname: Aboul-Enein
authors.forename: A
authors.initials: A
authors.lastname: al-Dakan
authors.forename: M A
authors.initials: MA
authors.lastname: Hannan
mesh_terms: D000818:Animals; D002851:Chromatography, High Pressure Liquid; D066298:In Vitro Techniques; D009152:Mutagenicity Tests; D009153:Mutagens; D010394:Penbutolol / Q000633:toxicity*; D011412:Propanolamines / Q000633:toxicity*; D051381:Rats; D012486:Salmonella typhimurium / Q000235:genetics; D013237:Stereoisomerism
chemical_list: D009153:Mutagens; D011412:Propanolamines; D010394:Penbutolol