Reactivity of diabetic urinary bladder to the cholinesterase inhibitor neostigmine.

To examine the effects of neostigmine, an acetylcholinesterase inhibitor that has been used to treat impaired bladder emptying on diabetic rat urinary bladder smooth muscle. Rat urinary detrusor muscle strips were suspended in organ baths containing Krebs' solution for isometric tension recording. Streptozotocin-diabetic (12 weeks) bladder tissue activity compared with control was assessed by using electrical field stimulation (EFS) in the presence and absence of the cholinesterase inhibitor, neostigmine. EFS-induced contractions; a major part of it is cholinergic in origin. Neostigmine significantly enhanced EFS-induced contractions in diabetic strips than control at all frequencies. Neostigmine caused concentration-dependent contractions of control and diabetic bladder tissues, which were completely abolished by atropine. Carbachol-induced bladder contraction was significantly reduced in diabetes. In diabetes mellitus, cholinesterase modulation (increase) may play a role in the development of inadequate bladder contraction, seen in later stage diabetic bladder dysfunction.