Cystometric changes in alloxan diabetic rats: evidence for functional and structural correlates of diabetic autonomic neuropathy.
Autonomic neuropathy and urinary bladder function were compared in Sprague-Dawley rats with alloxan-diabetes of 3 months duration, rats fed sucrose for 8 weeks, and rats examined 8 weeks after pelvic nerve surgical axotomy; normal age-matched rats were used as controls. All experimental interventions induced bladder hypertrophy with increased bladder weight. In diabetic and sucrose-fed animals, water intake and urinary output increased. Cystometric recordings of normal rats in vivo showed rhythmic contractions (1.25 +/- 0.25 contr/min) with threshold volume for micturition reflex at 0.51 +/- 0.04 ml. In diabetic rats, bladder contractions were irregular and of lower frequency (0.60 +/- 0.04 contr/min), while threshold volume was significantly higher (1.00 +/- 0.11 ml). Bladder contractions were normal in sucrose-fed animals, though threshold volume was markedly augmented (1.27 +/- 0.19 ml). Pelvic nerve surgical ablation abolished micturition reflex. In bladder strips excised post-mortem, contractile response to field stimulation was reduced in diabetic rats compared to control and sucrose-fed animals. Morphological examination of pelvic and hypogastric nerves revealed abnormalities characteristic of diabetic neuropathy only in diabetic rats. These data suggest that in alloxan-induced diabetes the decrease in the rate of bladder contraction is the result of autonomic neuropathy; while bladder hypertrophy in sucrose-fed rats appears to be an organ adaptation to hyperdiuresis.
Paro
M
M
Department of Neurocardiovascular Research, Fidia Research Laboratories, Abano Terme, Italy.
Italiano
G
G
Travagli
R A
RA
Petrelli
L
L
Zanoni
R
R
Prosdocimi
M
M
Fiori
M G
MG
D000496:Alloxan; D000818:Animals; D001342:Autonomic Nervous System Diseases / Q000473:pathology* / Q000503:physiopathology; D003921:Diabetes Mellitus, Experimental / Q000473:pathology*; D003929:Diabetic Neuropathies / Q000473:pathology* / Q000503:physiopathology; D004558:Electric Stimulation; D004724:Endoscopy; D007001:Hypogastric Plexus / Q000473:pathology; D008297:Male; D008854:Microscopy, Electron; D009420:Nervous System / Q000473:pathology; D010388:Pelvis / Q000294:innervation; D051381:Rats; D011919:Rats, Inbred Strains; D013268:Stimulation, Chemical; D001743:Urinary Bladder / Q000473:pathology*
D000496:Alloxan