title: Effect of diabetes on the ion pumps of the bladder.
abstract: OBJECTIVE
  To establish whether the activities of Na+/K+-adenosine triphosphatase (ATPase) and Ca2+-ATPases ion pumps in bladder smooth muscle are altered as a consequence of diabetes and, if so, how this might contribute to bladder cystopathy. Urinary bladder dysfunction is a common occurrence in patients with diabetes. Pressure generation requires calcium and cytosolic ATP. Activities of these pumps are responsible for calcium homeostasis.
  
  
  METHODS
  Rat urinary detrusor muscle strips were suspended in organ baths containing Krebs solution for isometric tension recording. Tissue responses to the Na+/K+-ATPase pump inhibitor, ouabain, the plasma membrane Ca2+ ATPase inhibitor, vanadate, and the sarcoplasmic reticulum Ca2+ ATPase inhibitor, cyclopiazonic acid (CPA), were examined from normal and streptozocin-induced diabetic rats for 2, 4, and 12 weeks.
  
  
  RESULTS
  Ouabain, vanadate, and CPA caused concentration-dependent contractions of bladder strips from diabetic and normal rats. The degree of contraction of diabetic bladder muscle was lower than that of controls. This reduction was a function of duration of diabetes. For ouabain, the reduction peaked at 2 weeks, with partial restoration to normal after diabetes induction. For vanadate and CPA, the reduction increased with the duration of diabetes.
  
  
  CONCLUSIONS
  The ion pumps are important modulators of bladder smooth muscle tone, and in a rat model of streptozotocin-induced diabetes, the activity of these pumps is impaired. Although this is only a single model of diabetes, these findings suggest that a defect in these pumps may be an important component of the development of diabetic bladder cystopathy.
authors.affiliation: Department of Biomedical Sciences, College of Nursing, Public Authority for Applied Education & Training, Kuwait. mustafaseham@yahoo.com
authors.forename: Seham
authors.initials: S
authors.lastname: Mustafa
mesh_terms: D000818:Animals; D001835:Body Weight; D003921:Diabetes Mellitus, Experimental / Q000150:complications / Q000503:physiopathology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D066298:In Vitro Techniques; D007211:Indoles / Q000494:pharmacology; D016623:Ion Pumps / Q000187:drug effects / Q000502:physiology*; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000503:physiopathology*; D010042:Ouabain / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D001743:Urinary Bladder / Q000503:physiopathology*; D001745:Urinary Bladder Diseases / Q000209:etiology / Q000503:physiopathology; D014638:Vanadates / Q000494:pharmacology
chemical_list: D004791:Enzyme Inhibitors; D007211:Indoles; D016623:Ion Pumps; D014638:Vanadates; D010042:Ouabain; C000543:cyclopiazonic acid