STUDIES OF THE PATHOPHYSIOLOGY OF IDIOPATHIC DETRUSOR INSTABILITY: THE PHYSIOLOGICAL PROPERTIES OF THE DETRUSOR SMOOTH MUSCLE AND ITS PATTERN OF INNERVATION

Purpose: Idiopathic detrusor instability (IDI) is a common cause of lower urinary tract storage symptoms, such as urgency, frequency and urge incontinence. We have investigated the in vitro properties and pattern of innervation of the detrusor from patients with this condition.Materials and Methods: Full thickness bladder specimens were obtained perioperatively from 14 patients with IDI and from 14 cadaveric controls undergoing transplant organ retrieval. Isolated detrusor smooth muscle strips were mounted in organ baths for isometric tension recording. Frequency-response curves to electrical field stimulation (EFS) (1 Hz to 50 Hz) and concentration response curves for carbachol (10−7 M to 5 × 10−4 M) and potassium (12 mM to 120 mM) were constructed. Acetylcholinesterase histochemistry and immunohistochemistry for both phosphorylated and non-phosphorylated neurofilaments was carried out on frozen sections of control and IDI bladders.Results: IDI strips developed greater spontaneous tone (0.25 gm./mg. vers...