Clin Chem. 1987 Jun;33(6):819-20.
Detection of interference by cyclobenzaprine in liquid-chromatographic assays of tricyclic antidepressants.

Puopolo PR, Flood JG.

We evaluated a technique for detecting cyclobenzaprine interference with liquid-chromatographic assays for tricyclic antidepressants. The technique involves dual-wavelength absorbance monitoring of the column effluent at 214 and 254 nm. Ratios of analyte peak heights at each wavelength are used to check for the presence of co-eluting interferences. With this technique, one can detect interference with an amitriptyline assay caused by 10 micrograms of cyclobenzaprine per liter.

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Int J Cancer. 1975 Nov 15;16(5):787-97.
Epoxides metabolically produced from some known carcinogens and from some clinically used drugs. I. Differences in mutagenicity.

Glatt HR, Oesch F, Frigerio A, Garattini S.

The epoxide metabolites of two clinically used drugs and an experimental psychotropic agent, carbamazepine 10,11-oxide, cyproheptadine 10,11-oxide and cyclobenzaprine 10,11-oxide, were fully devoid of any mutagenic activity under conditions where K-region-epoxide metabolites of some known carcinogens, such as benzo(a)pyrene, proved to be potent frameshift mutational agents for Salmonella typhimurium TA 1537 and TA 1538. All epoxides tested were non-mutagenic for TA 1535, designed to detect substitution mutations. The 10,11-epoxides of the three drugs, carbamazepine, cyproheptadine and cyclobenzaprine, were not cytotoxic to any of the bacterial tester strains used, precluding that mutagenicity might have been overshadowed by cytotoxicity. When the mutagen, precursor, benzo(a)pyrene, was incubated together with TA 1537 and a mammalian microsomal preparation in the presence of a system generating the co-factor necessary for mono-oxygenase activity, activation to mutagenic species was observed which was dramatically increased in the presence of a potent epoxide hydratase inhibitor, 1,1,1-trichloropropene 2,3-oxide, suggesting epoxide(s) as the (or one of the) mutagenically active species metabolically produced in situ. None of these effects was observed with the three medical drugs. Moreover, the observation that the alkene oxide 4-phenylstyrene 7,8-oxide is mutagenic to the two strains TA 1537 and TA 1538 but the K-region arene oxide derived from 7,12-dimethylbenz(a)anthracene is inactive for the latter strain indicates that epoxidation of an aromatic double bond of a polycyclic hydrocarbon is neither a necessary nor a satisfying condition for frameshift mutagenesis to occur.

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Pharmacol Biochem Behav. 1979 Jun;10(6):947-9.
Cyclobenzaprine [Flexeril] and ethanol interaction.

Messiha FS, Barnes CD.

The effects of cyclobenzaprine, a tricyclic compound, on the central depressant action of ethanol and on hepatic ethanol metabolizing enzymes were studied in rodents. Administration of cyclobenzaprine, 5 mg/kg, IP, 30 min prior to a narcotic dose of ethanol solution, 5 g/kg, IP, enhanced ethanol-produced narcosis in mice. This effect was greater in male than in female mice. Cyclobenzaprine [Flexeril] inhibited endogenous rat liver alcohol dehydrogenase in vitro in the concentration range between 10(-5) M and 10(-6)M. Cyclobenzaprine [Flexeril] exerted little effect on hepatic aldehyde dehydrogenase in vitro. The results suggest that cyclobenzaprine possesses depressant properties and inhibition of liver alcohol dehydrogenase may underlie the observed behavioral response studied. It is concluded that alteration of endogenous liver alcohol dehydrogenase by certain tricyclic antidepressant drugs may be involved in the mechanism(s) of their toxic interaction with ethanol.

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J Chromatogr. 1977 Jan 21;131:357-63.
Determination of various drugs in rodent diet mixtures.

Hucker HB, Stauffer SC.

Methods employing solvent extraction, thin-layer chromatography, gas-liquid chromatography, and UV spectrophotometry are described for the quantitative determination of halofenate, cyclobenzaprine and sulindac in rodent diet mixtures. Halofenate was hydrolyzed to its free acid derivative and converted to a methyl ester prior to assay. The drugs were shown to be stable when stored in food mixtures at room temperature for seven days. Diet mixtures containing the three drugs were demonstrated to be uniformly mixed by the procedure employed.

Online pharmacy ref source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=558222&dopt=Abstract cyclobenzaprine Flexeril