Functional response of bladder strips from streptozotocin diabetic rats depends on bladder mass.
OBJECTIVE
We investigated the relationship of bladder mass to responses to electrical field stimulation and adrenergic agonists in diabetic rat bladders.


METHODS
Longitudinal strips were removed from the ventral and dorsal detrusor of age matched control, 2-month diabetic and sucrose drinking rats. Contractile responses to electrical field stimulation, KCl and phenylephrine, and relaxation in response to norepinephrine and isoproterenol were measured.


RESULTS
Bladders from sucrose drinking and diabetic rats weighed significantly more than those of controls. Diabetic rats were divided into 2 groups with the bladder weighing less than or greater than 265 mg. Strips from small diabetic bladders were generally more responsive to field stimulation and norepinephrine than those from control or sucrose drinking rats. Conversely decreased function was especially apparent in dorsal strips from large diabetic bladders. Ventral strips were significantly more sensitive to the relaxant actions of norepinephrine and isoproterenol than dorsal strips.


CONCLUSIONS
Our results suggest that the responsiveness of diabetic rat bladder to electrical field stimulation and adrenergic agonists is related to bladder mass, analogous to observations after partial outlet obstruction. Decreased function was particularly apparent in dorsal strips from diabetic rats with a large bladder.
Bezuijen
Martina W F
MW
Department of Basic and Pharmaceutical Sciences, Albany College of Pharmacy and Division of Urology, Albany Medical College, Albany, New York, USA.
Levendusky
Mark C
MC
Longhurst
Penelope A
PA
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D003921:Diabetes Mellitus, Experimental / Q000473:pathology / Q000503:physiopathology*; D004558:Electric Stimulation; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009126:Muscle Relaxation / Q000187:drug effects; D009638:Norepinephrine / Q000494:pharmacology; D009929:Organ Size; D010656:Phenylephrine / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D001743:Urinary Bladder / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology*
D000316:Adrenergic alpha-Agonists; D000318:Adrenergic beta-Agonists; D010656:Phenylephrine; D011189:Potassium Chloride; D007545:Isoproterenol; D009638:Norepinephrine