Abstract
When the brains of Wistar rats were extracted 1 1/4 hours after single intraperitoneal injections of radio-active imipramine some desmethylimipramine (DMI) was always found, together with comparable amounts of iminodibenzyl (IdB) and 2 hydroxyimipramine. The total radioactivity recovered from brain, (usually less than 0.2 % of dose) did not rise on repeated daily injection but then proportions of DMI and IdB tended to be higher.
Brain slices incubated for 2 hours at 37° C with radioactive imipramine produced DMI, IdB, and some didesmethylimipramine, but no hydroxylated metabolites. Liver slices produced more DMI, less IdB, a fair amount of 10-hydroxy DMI and comparable 2-hydroxyimipramine. Heart, kidney, lung and gut slices were also active in varying degrees.
These findings are consistent with at least two different metabolic hypotheses of the way imipramine exerts its antidepressant action in man.
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Abbreviations
- I:
-
imipramine
- DMI:
-
desmethylimipramine
- DDMI:
-
dides methylimipramine
- IdB:
-
iminodibenzyl
- 2 OH-I, 2 OH-IdB:
-
two-hydroxy-imipramine etc.
- 10 OH-DMI:
-
ten-hydroxy-desmethylimipramine
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Crammer, J.L., Rolfe, B. Metabolism of 14C-imipramine. Psychopharmacologia 18, 26–37 (1970). https://doi.org/10.1007/BF00402381
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DOI: https://doi.org/10.1007/BF00402381