ALTERATIONS TO THE ELECTROPHYSIOLOGY OF ISOLATED HUMAN DETRUSOR SMOOTH-MUSCLE CELLS IN BLADDER DISEASE

The aim of the study was to investigate the properties of the inward c alcium current (i(Ca)) obtained from isolated human detrusor smooth mu scle cells in different pathological conditions using the whole-cell p atch-clamp technique. Previous experiments on field stimulated detruso r muscle strips have shown specific differences associated with hypert rophy and detrusor instability. As i(Ca) plays an important role in ex citation-contraction coupling in this tissue, it was therefore of inte rest to determine if i(Ca) was altered in the above disease states. It was found that myocytes from patients with prostatic symptoms had a s ignificantly increased surface area and that the kinetics of i(Ca) wer e also significantly altered in these cells. Although the surface area of cells from patients with idiopathic instability and detrusor hyper reflexia was also significantly increased, the kinetics of i(Ca) were altered in different ways. These alterations to i(Ca) will alter the a ction potential configuration and its propagation through the muscle m ass.