Effects of chelator treatment on aorta and corpus cavernosum from diabetic rats.
Transition-metal catalyzed reactions contribute to oxidative stress, which has been implicated in the pathogenesis of diabetic complications. The aim was to evaluate the effects of treatment with the transition metal chelator trientine on endothelium-dependent relaxation of aorta and corpus cavernosum from streptozotocin-induced diabetes of 8 weeks duration in rats. Effects on cavernosum autonomic innervation were also examined. Diabetes caused a 30.1 +/- 3.8% reduction in maximum aorta endothelium-dependent relaxation to acetylcholine (ACh), which was markedly attenuated (72.7 +/- 10.6%) by trientine treatment. Reversal treatment (4 weeks untreated diabetes, 4 weeks trientine) did not effect endothelium-dependent relaxation compared with aortas from rats with 4 weeks of diabetes, however, there was a 22.5 +/- 6.2% improvement compared with 8 weeks of diabetes. Eight weeks of diabetes caused a 41.5 +/- 6.6% reduction in corpus cavernosum endothelium-dependent maximum relaxation to ACh that was 70.1 +/- 16.9% prevented by trientine. Cavernosum nonadrenergic, noncholinergic (NANC) nerve stimulation caused frequency-dependent relaxation to a maximum of 40.9 +/- 2.4%, which was reduced by diabetes to 24.2 +/- 2.1%. Trientine partially prevented this deficit, maximum relaxation being 31.9 +/- 2.3%. Thus, metal chelator treatment has beneficial effects on aorta and cavernosum endothelium-dependent relaxation and on cavernosum NANC innervation.
Keegan
A
A
Department of Biomedical Sciences, University of Aberdeen, Foresterhill, Scotland, United Kingdom.
Cotter
M A
MA
Cameron
N E
NE
D000109:Acetylcholine / Q000494:pharmacology; D000818:Animals; D001011:Aorta / Q000187:drug effects*; D001786:Blood Glucose / Q000378:metabolism; D002614:Chelating Agents / Q000494:pharmacology*; D003921:Diabetes Mellitus, Experimental / Q000503:physiopathology; D004558:Electric Stimulation; D004730:Endothelium, Vascular / Q000187:drug effects; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D005996:Nitroglycerin / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology; D010413:Penis / Q000187:drug effects* / Q000294:innervation; D010656:Phenylephrine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D014266:Trientine / Q000494:pharmacology* / Q000627:therapeutic use; D014665:Vasodilator Agents / Q000494:pharmacology
D001786:Blood Glucose; D002614:Chelating Agents; D014665:Vasodilator Agents; D009599:Nitroprusside; D010656:Phenylephrine; D005996:Nitroglycerin; D000109:Acetylcholine; D014266:Trientine