The effect of diabetes mellitus on α1-adrenergic receptor subtypes in the bladder of rats.
OBJECTIVE
To detect the possible alterations on density or sensitivity of α1-adrenergic subtypes in diabetic bladder by reverse transcriptase-polymerase chain reaction technology and in vitro studies.


METHODS
Experimental diabetes was induced by administration of streptozotocin with a single injection through the tail vein. Rats were divided into control and diabetic groups. Contractile responses of bladder strips from each group were obtained for postassium chloride, adenosine triphosphate, and electrical field stimulation (0.5-32 Hz) in organ bath. Electrical field stimulation responses of strips were evaluated in the presence of PPADS (nonselective P2 antagonist), atropine (cholinergic antagonist), 5 MU (α-1a-adrenergic antagonist), BMY-7378 (α-1d-adrenergic antagonist), and finally CED (α-1b-adrenergic antagonist). mRNA expression of α1-adrenergic subtypes was determined for each group.


RESULTS
The difference between contractile responses related to electrical field stimulation with incubation with PPADS, atropine, 5 MU, BMY-7378, and CED, respectively, was not significant in the control and diabetic groups (P > .05). The electrical field stimulation responses of strips at 0.5-2 Hz without incubation were significantly different between the control and diabetic groups (P < .05). The contractile responses of strips with PPADS + atropine + 5 MU and BMY-7378 incubations in the diabetic group were significantly lower than in the control group in all doses (P < .05), The mRNA expression of α-1a-adrenergic in the diabetic group was significantly lower than in the control group (P < .05). No change was found in the expression of mRNA of α-1b-adrenergic.


CONCLUSIONS
These results support the probability of changes in presynaptic and autonomic receptor sensitivity. We believe that α-1a-adrenergic and α-1d-adrenergic subtypes should be kept in mind in the treatment of diabetic cystopathy.
Baskent University, Konya Research and Training Hospital, Department of Urology, Konya, Turkey. drugonulalan@yahoo.com
Umut
U
Gonulalan
Murat
M
Kosan
Gaye
G
Hafez
Ebru
E
Arıoglu
Ozgur
O
Akdemir
Bulent
B
Ozturk
Serap
S
Gur
Mesut
M
Cetinkaya
D000255:Adenosine Triphosphate / Q000494:pharmacology; D000818:Animals; D001786:Blood Glucose; D003920:Diabetes Mellitus / Q000097:blood / Q000139:chemically induced / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects / Q000378:metabolism; D011189:Potassium Chloride / Q000494:pharmacology; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D018340:Receptors, Adrenergic, alpha-1 / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D018709:Statistics, Nonparametric; D013311:Streptozocin; D001743:Urinary Bladder / Q000378:metabolism* / Q000503:physiopathology
D001786:Blood Glucose; D012333:RNA, Messenger; D018340:Receptors, Adrenergic, alpha-1; D013311:Streptozocin; D011189:Potassium Chloride; D000255:Adenosine Triphosphate