Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0344307 (analgesia)
 28,200 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The analgesic effect of acute or chronic nortriptyline, amitriptyline and their effects on morphine induced analgesia were evaluated in the rat. Clomipramine and amitriptyline, but not Nortriptyline, induce analgesia, while all potentiate the effect of morphine when administered acutely. The analgesic effect of clomipramine is blunted by both the serotonin antagonist metergoline and the opiate receptor blocker naloxone, thus indicating an involvement of both the serotoninergic and endogenous opioid system. The involvement of the serotoninergic system is confirmed by the similar results obtained with the serotonin precursor 5-hydroxytryptophan administered alone or together with morphine. A relation between the serotoninergic and the endogenous opioid systems is also shown by the increase in hypothalamic beta-endorphin concentrations elicited by all the drugs used after acute or chronic treatment, with the only exception of nortriptyline, that has been shown to exert its effects mainly through the noradrenergic system. In conclusion, the analgesic effect of clomipramine and amitriptyline and their potentiation of morphine induced analgesia seems to be related to an activation of the endogenous opioid system mediated by serotonin.
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PMID:A role for serotonin and beta-endorphin in the analgesia induced by some tricyclic antidepressant drugs. 295 43

The purpose of this study was to evaluate the skin permeation of tricyclic antidepressants (TCAs) with propamine moiety to select candidates for the development of topical analgesics to treat cutaneous pain. We sought to establish the structure-permeation relationship (SPR) of topical TCAs. The lipophilicity, melting point, and aqueous solubility were determined to develop the physicochemical characterization. The TCA permeation into pig and nude mouse skins was estimated using Franz diffusion cell. TCAs and lidocaine were comparatively examined for cutaneous analgesia by pinprick assay. Cutaneous tolerance to TCAs was assessed using nude mouse skin. The skin deposition increased following the increase of lipophilicity after excluding the effect of solubility, with clomipramine exhibiting the highest skin retention. A contrary result was observed for TCA penetration into the receptor. Of the permeants tested, clomipramine demonstrated the best skin-targeting ability. Nortriptyline and clomipramine demonstrated selective uptake into the hair follicles, exhibiting a 2.5-fold higher follicular accumulation than desipramine. Replacement of nitrogen with carbon in the seven-member ring increased skin absorption. The tertiary amine TCAs demonstrated higher absorption than the secondary amine TCAs. The position of the double bond also affected skin transport. Topical clomipramine had a longer duration of analgesic action than lidocaine (240min versus 60min). Exploring the SPR revealed that clomipramine could be an analgesic candidate drug for future development.
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PMID:Exploring the structure-permeation relationship of topical tricyclic antidepressants used for skin analgesia. 2834 73