Effect of botulinum toxin on autonomic regulation of normal and obstructive urinary bladder in rats

Effects of botulinum toxin injection into detrusor on autonomic regulation were studied in normal and after 1 month of infravesical obstruction modeling. Investigations were made in acute experiments during infusion cystometry, in which synchronous registration was performed of detrusor pressure and bladder impedance with highly sensitive soft and hardware complex (“Biola”). Analysis of impedance variations were made by Fourier transform in a range of 0.05 - 15 Hz. Evaluation of autonomic and parasympathetic nerve regulation was made basing on changes of spectral peaks of impedance on a very low frequency (0.1 Hz) and breath rate (~ 1 Hz) and also on relation of these peaks. Obtained results of oppression of both peeks in botulin-ized rats at rest bladder neurogenic activity oppression, and relation between Mayer peak and respiratory peak in impedance specter of bladder showed shift of sympathi-covagus balance into sympathetic prevalence side. In experimantal rats injected with botulinum toxin lower values of detrusor pressure were observed at rest and during all the phases of infusion cystometry in comparison with rats without botulinum toxin injection, with bladder pressure higher in rats with infra-vesical obstruction even after botulotoxin injection. On the basis of revealed changes of neurogenic activity of bladder, evaluated by peaks of impedance range, characterizing autonomic and parasympathetic regulation, the reasons of high miogenic tone of bladder in rats with infravesical obstruction is discussed.