HSTOPATHOLOGICAL AND ULTRASTRUCTURAL CHANGES ASSOCIATED WITH, SUBARACHNOID, EPIDURAL AND INTERPLEURAL NEUROLYSIS IN DOGS

Abstract

This study was carried out to domenstrate and compare the neurotoxic effects of different neurolytic agents namely phenol, chlorocresol, alcohol and glycerine through histopathological and electron microscopic examinations. The work was done on 55 adult healthy male and femal mongrel dogs. The animals were classified according to the site of neural blockade, into three groups 1, subarachnoid 2, epidural and 3, interpleural group. Apical heart rate and respiratory rate were monitored before injection and 1,2,5,10,15,20,25 and 30 minutes after injection. Any abnormal movements following injection were recorded. A statistical significance increase in both mean heart rate and mean respiratory rate following subarachnoid phenol and chlorocresol neurolysis respectively were recorded. Hisopathological and electron microscopic examinations of the subarachnoid group revealed that chlorocresol is the most potent neurotoxic drug followed by phenol then alcohol. Glycerine was the least neurotoxic drug. Histopathological and electron microscopic examinations revealed that epidural phenol is the most potent neurotoxic drug in this group followed by alcohol. Glycerine was the least neurotoxic drug. As regards the route of administration, subarachnoid approach was found to allow the drug to produce its maximum neutrotoxic effect followed by epidural route. A statistically significant increase in both mean heart rate and mean respiratory rate following interpleural phenol injection was observed. Histopathological and electron microscopic examiantions revealed that interpleural phenol injection has a minimal tissue effect.