Abstract
1 Conditions have been worked out for a reliable estimation of the cataleptic activity of delta'-trans-tetrahydrocannabinol (THC) after oral administration to mice, using the ring test over a period of 6 h. 2 By this method, the activity of cannabis herb and 5 crude fractions were measured against THC; at the same time the THC contents were determined chemically. 3 The B/C ratio (biological activity divided by chemical assay) was calculated for each. With cannabis herb the value was 3.3 and with extracts prepared with ethanol or 70% ethanol the values ranged from 3.2 to 7.1, indicating that in all samples the activity was much higher than would be expected from their THC content. 4. The cannabinoids were completely extracted from a sample of herb using petroleum spirit and the marc examined for a possible synergist. Surprisingly, it contained a powerful inhibitor of the action of THC, which could be restored by intraperitoneal prostaglandin E2 (3 microgram/kg). Some crude fractions had inhibitory activities about 10 times that of aspirin. 5 In contrast, the petroleum spirit extract (referred to in 4) had a surprisingly high B/C ratio of 23, indicating that a powerful synergist of THC activity is present. 6 The net effect of the herb and ethanol extracts is probably due to a balance of synergist and inhibitor.
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- COHEN H., VAN RAMSHORST J., TASMAN A. Consistency in potency assay of tetanus toxoid in mice. Bull World Health Organ. 1959;20:1133–1150. [PMC free article] [PubMed] [Google Scholar]
- Carlini E. A., Karniol I. G., Renault P. F., Schuster C. R. Effects of marihuana in laboratory animals and in man. Br J Pharmacol. 1974 Feb;50(2):299–309. doi: 10.1111/j.1476-5381.1974.tb08576.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fairbairn J. W., Liebmann J. A., Rowan M. G. The stability of cannabis and its preparations on storage. J Pharm Pharmacol. 1976 Jan;28(1):1–7. doi: 10.1111/j.2042-7158.1976.tb04014.x. [DOI] [PubMed] [Google Scholar]
- Fairbairn J. W., Liebmann J. A. The cannabinoid content of Cannabis sativa L grown in England. J Pharm Pharmacol. 1974 Jun;26(6):413–419. doi: 10.1111/j.2042-7158.1974.tb09306.x. [DOI] [PubMed] [Google Scholar]
- Fairbairn J. W., Liebmann J. A. The extraction and estimation of the cannabinoids in Cannabis sativa L. and its products. J Pharm Pharmacol. 1973 Feb;25(2):150–155. doi: 10.1111/j.2042-7158.1973.tb10609.x. [DOI] [PubMed] [Google Scholar]
- Fairbairn J. W., Pickens J. T. The effect of conditions influencing endogenous prostaglandins on the activity of delta'-tetrahydrocannabinol in mice. Br J Pharmacol. 1980 Jul;69(3):491–493. doi: 10.1111/j.1476-5381.1980.tb07039.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Fairbairn J. W., Pickens J. T. The oral activity of delta'-tetrahydrocannabinol and its dependence on prostaglandin E2. Br J Pharmacol. 1979 Nov;67(3):379–385. doi: 10.1111/j.1476-5381.1979.tb08691.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- GADDUM J. H. Bioassays and mathematics. Pharmacol Rev. 1953 Mar;5(1):87–134. [PubMed] [Google Scholar]
- Isbell H., Gorodetzsky C. W., Jasinski D., Claussen U., von Spulak F., Korte F. Effects of (--)delta-9-trans-tetrahydrocannabinol in man. Psychopharmacologia. 1967;11(2):184–188. doi: 10.1007/BF00401256. [DOI] [PubMed] [Google Scholar]
- Isbell H. II. Clinical pharmacology of marihuana. Pharmacol Rev. 1971 Dec;23(4):337–338. [PubMed] [Google Scholar]
- Korte F., Haag M., Claussen U. Tetrahydrocannabinolcarboxylic acid, a component of hashish. 1. Angew Chem Int Ed Engl. 1965 Oct;4(10):872–872. doi: 10.1002/anie.196508721. [DOI] [PubMed] [Google Scholar]
- Mechoulam R., Ben-Zvi Z., Yagnitinsky B., Shani A. A new tetrahydrocannabinolic acid. Tetrahedron Lett. 1969 Jun;(28):2339–2341. doi: 10.1016/s0040-4039(01)88158-2. [DOI] [PubMed] [Google Scholar]
- Thompson W. R. USE OF MOVING AVERAGES AND INTERPOLATION TO ESTIMATE MEDIAN-EFFECTIVE DOSE: I. Fundamental Formulas, Estimation of Error, and Relation to Other Methods. Bacteriol Rev. 1947 Jun;11(2):115–145. [PMC free article] [PubMed] [Google Scholar]