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Isotope effect studies on the dehydrogenation of Δ1-tetrahydrocannabinol in the rat

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  • Chimica, Biochimica
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Summary

Isotope effect studies on the metabolic dehydrogenation of Δ1-tetrahydrocannabinol in rats are described and its is shown that this process is confined to a very short period following i.v. administration. The implications of this finding are discussed.

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References

  1. R. Mechoulam, A. Shani, H. Edery and Y. Grunfeld, Science169, 611 (1970).

    Article  CAS  PubMed  Google Scholar 

  2. M. Fermandes, A. Schabarek, H. Coper and R. Hill, Psychopharmacologia38, 329 (1974); R. N. Takahashi and I. G. Karniol, Psychopharmacologia41, 277 (1975); and cited references.

    Article  Google Scholar 

  3. N. K. McCallum, Experientia31, 957 (1975).

    Article  CAS  PubMed  Google Scholar 

  4. N. K. McCallum, B. Yagen, S. Levy and R. Mechoulam, Experientia31, 520 (1975).

    Article  CAS  PubMed  Google Scholar 

  5. S. Aronoff, in: Techniques and Radiobiochemistry, p. 9. Iowa State College Press, 1956.

  6. 3H-Δ1-THC labelled at C(3), was the kind gift of Dr S. Burstein of the Worcester Foundation for Experimental Biology;14C-Δ1-THC labellet at C(6′) and C(4′) in the aromatic ring was kindly supplied by Dr M. Braude of the National Institute on Drug Abuse, Maryland, USA.

  7. J. A. Vinson and J. E. Hooyman, J. Chromatogr.106, 196 (1975).

    Article  CAS  Google Scholar 

  8. Purities of the cannabinoids were: Δ1-THC contained 0.4% CBN by standard glc techniques and 0.1% CBN using varied exposures of a thin layer chromatogram to photographic plates; the CBN was 99.5% pure with ca. 0.1% Δ1-THC by glc.

  9. Male Sprague-Dawley rats (130–150 g) were used with 1 mg CBN and/or 1 mg3H,14C-Δ1-THC (ca. 4 μCi in total) per administration.

  10. The propylene glycol showed a tendency to absorb moisture from the air causing the solution to form a cloudy, microsuspension of cannabinoid. Results using such a solution tended to be erratic (generally higher) unless the cannabinoid was solubilized by further warming or addition of traces of acetone and remixed.

  11. Donald L. Horrocks, Applications of Liquid Scintillation Counting. Academic Press, New York and London 1974.

    Google Scholar 

  12. On the basis of blood level data6 it can be argued that up to 35 sec after administration the injection plug is moving from the tail to the heart, and thus mixing (and therefore metabolism) can only take place after it reaches the heart, i.e. between 35 and 40 sec after administration. If this is the case the latter period represents not 42, but over 300 times the initial period during which metabolism is taking place.

  13. E. R. Garrett and C. A. Hunt, J. pharm. Sci.63, 1056 (1974).

    Article  CAS  PubMed  Google Scholar 

  14. W. H. Oldendort, Proc. Soc. exp. Biol. Med.147, 813 (1974).

    Article  Google Scholar 

  15. A. Goldstein, L. Aronow and S. M. Calman, Principles of Drug Action: The basis of Pharmacology, 2nd ed., p. 190. John Wiley & Sons Inc., 1974.

  16. Pharmacology of Marihuana, p. 63. Ed. M. C. Braude and S. Szara. Raven Press, New York 1975.

    Google Scholar 

  17. Thiopental A. Goldstein and L. Aronow, J. Pharmac. exp. Ther.128, 1 (1960) provies ans analogy with Δ1-THC. In this case lower lipophilicity results in less protein binding and would be expected to result in much less retention of the drug by the brain.

    CAS  Google Scholar 

  18. L. Lemberger, N. R. Tamarkin, J. Axelod and I. J. Kopin, Science173, 72 (1971).

    Article  CAS  PubMed  Google Scholar 

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The authors are grateful for generous fifts of3H-Δ1-THC from Dr S. Burstein (Worcester Foundation for Experimental Biology, Massachusetts), and of14C-Δ1-THC from the National Institute on Drug Abuse. The authors thank the staff of the Small Animal Unit, Wallaceville Research Centre for their cooperation, and the U.S. National Institute on Drug Abuse for their support.

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McCallum, N.K., Gugelmann, A., Brenninkmeijer, C.A.M. et al. Isotope effect studies on the dehydrogenation of Δ1-tetrahydrocannabinol in the rat. Experientia 33, 1012–1014 (1977). https://doi.org/10.1007/BF01945939

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