In vitro motility investigations and electron microscopic observations on children's upper urinary tract muscle wall.

This study was performed as a part of a longer research programme on urinary tract smooth muscle layer in children. All the children whose samples were investigated underwent surgery for urinary tract malformations. Specimens were taken from different segments of upper urinary tract during surgical intervention. Specimens were investigated by either in vitro motility tests or electron microscopy or both of them. Basic patterns of tissue strips were recorded after incubation of varying duration and then tested by administering neurotransmitter agents like noradrenaline and acetylcholine-bromide. Microstructure of samples were examined electron microscopically. Investigations were performed in order to find correlation between microarchitecture and motility patterns of urinary muscle wall. Factors influencing urinary muscle motility, characteristic features of impaired musculature and its possible regeneration are discussed too. Microhistological deteriorations inhibit spontaneous smooth muscle motility but muscle contractility proved by administering noradrenaline and acetylcholine-bromide remained in some extent. Taking into consideration that smooth muscle is able to regenerate and rebuild close contacts pediatric surgeon and urologist should spare kidney parenchyma as far as it is possible.