Repeated intrathecal injections of dezocine produce antinociception without evidence for neurotoxicity in the rat: a study of morphometric evaluation of spinal cord histology.
This study was designed to determine the antinociceptive and spinal cord histologic effects of a new agonist/antagonist opioid drug dezocine. This drug was injected intrathecally in rats at a dose of 50 or 125 micrograms twice daily for 14 days. The tail-flick test showed that the antinociceptive effect declined gradually, with no detectable effects by day 14. Quantitative histologic techniques and light and electron microscopy showed that neither dose, compared with vehicle, created any morphologic changes in the spinal cord that could be attributed to a neurotoxic or otherwise degenerative effect of the drug. In conclusion, dezocine is a drug that gives rise to sustained antinociceptive effects when administered intrathecally and causes no morphologic changes in the rat spinal cord that could be indicative of neurotoxic potential.
Svensson
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BA
Department of Anatomy, Uppsala University, Sweden.
Alari
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L
Post
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C
D000700:Analgesics / Q000008:administration & dosage / Q000494:pharmacology / Q000633:toxicity*; D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects; D001835:Body Weight / Q000187:drug effects; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002404:Catheterization / Q000009:adverse effects; D003516:Cycloparaffins / Q000008:administration & dosage / Q000494:pharmacology / Q000633:toxicity*; D004353:Drug Evaluation, Preclinical; D007249:Inflammation / Q000209:etiology; D007278:Injections, Spinal; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009619:Nociceptors / Q000187:drug effects*; D010147:Pain Measurement / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D013116:Spinal Cord / Q000166:cytology / Q000187:drug effects* / Q000473:pathology; D013118:Spinal Cord Diseases / Q000139:chemically induced* / Q000473:pathology; D013764:Tetrahydronaphthalenes
D000700:Analgesics; D019086:Bridged Bicyclo Compounds, Heterocyclic; D003516:Cycloparaffins; D013764:Tetrahydronaphthalenes; C010827:dezocine