| Autor: |
Fermino S, Lizarte, Marcelo, Morgueti, Carlos R, Tirapelli, Mario A, Claudino, Paulo R B, Evora, Paulo C, Novais, Daniela P C, Tirapelli, Andrea C, Celotto, Verena K, Capellini, Fabia P M, Celini, Silvio, Tucci, Adauto J, Cologna, Edson, Antunes, Antonio C P, Martins, Luis F, Tirapelli |
| Rok vydání: |
2010 |
| Předmět: |
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| Zdroj: |
BJU international. 105(11) |
| ISSN: |
1464-410X |
| Popis: |
To investigate the effects of chronic ethanol consumption and diabetes on nitric oxide (NO)-mediated relaxation of cavernosal smooth muscle (CSM).Male Wistar rats were divided into four groups: control, isocaloric, diabetic and ethanol-diabetic. The CSMs were mounted in organ chambers for measurement of isometric tension. Contraction of the strips was induced by electrical field stimulation (EFS, 1-32 Hz) and phenylephrine. We also evaluated the effect of ethanol consumption on the relaxation induced by acetylcholine (ACh; 0.01-1000 micromol/L), sodium nitroprusside (SNP, 0.01-1000 micromol/L) or EFS (1-32 Hz) in strips pre-contracted with phenylephrine (10 micromol/L). Immunoexpression of endothelial NO synthase (eNOS) and inducible NOS (iNOS) was also accessed.The endothelium-dependent relaxation induced by ACh was decreased in CSM from ethanol-diabetic rats when compared with the controls, with a mean (sem) of 21 (4) vs 37 (2)%. Similarly, the potency and maximal responses induced by SNP were reduced in the ethanol-diabetic [3.97 (0.38) and 85 (1)%, respectively] and diabetic groups [3.78 (0.56) and 81 (2)%, respectively] when compared with the controls [5.3 (0.22) and 90 (3)%, respectively] and isocaloric [5.3 (0.19) and 92 (1)%, respectively] groups. Noradrenergic nerve-mediated contractions of CSM in response to EFS were increased in rats from ethanol-diabetic and diabetic groups when compared with the control and isocaloric groups. Conversely, there were no differences in EFS-induced relaxation among the groups. The immunostaining assays showed overexpression of eNOS and iNOS in the CSM from diabetic and ethanol-diabetic rats when compared with the control and isocaloric rats.There was an impairment of relaxation of CSM from ethanol-diabetic and diabetic rats that involved a decrease in the NO-cyclic guanosine monophosphate signalling pathway by endothelium-dependent mechanisms accompanied by a change in the CSM contractile sensitivity. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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