Effect of atropine and diclofenac on the contractility of dog's vesico-urethral smooth muscls vitro

ABSTRACT

Smooth muscle preparations from various parts of the vesicourethral system of dogs and cats were used. These were suspended in Tyrode's solution at 37°C, bubbled with carbogen. The contractile response was recorded through an isotonic muscle transducer on a chartmover. It was observed that while the response to the ganglion stimulant Dimethyl phenyl piperazinium [D, M.P.P] is variable i.e. contraction, relaxation or no response acetyl choline induced contraction in all specimens. In addition atropine escape phenomenon was not uniformly distributed.Also alpha and beta adrenergic blockers in combination with prostaglandins synthetase inhibitor can induce complete block in response to acetyl choline in areas where atropine escape phenomenon was observed.These observations, in addition to the constant demonstration of atropine escape phenomenon in our in vivo experiments, suggest that a central mechanism plays an important role in atropine escape phenomenon and this phenomenon is variable in our in vitro experiments. Also, prostaglandins may be partially responsible for atropine resistance of the detrusor