Male Sexual DysfunctionChronic Ethanol Consumption Induces Cavernosal Smooth Muscle Dysfunction in Rats
Section snippets
Experimental Design
Male Wistar rats with body mass in the range 200-230 g were randomly divided into 2 groups (control and ethanol) at the start of the experiment. Rats in the control group received tap water ad libitum and those in the ethanol group received 20% vol/vol ethanol in their drinking water.12 The ethanol-treated group was submitted to a brief and gradual adaptation period: the animals received 5% ethanol in their drinking water in the first week, 10% in the second week, and 20% in the third week. The
Effects of Chronic Ethanol Consumption on Mass Body Weight and KCl-induced Contraction
Before treatment, mean body masses of the rats were 220 ± 6 g (control) and 224 ± 5 g (ethanol-treated). After treatment for 4 weeks, no variation in body mass was observed in animals across the 2 experimental groups: 520 ± 11 g (control) and 478 ± 17 g (ethanol-treated) (Student's t-test).
When tissues were contracted with KCl at 80 mmol L−1, the tensions were similar in both groups, with contractions of 2.4 ± 0.2 mN (n = 6) in ethanol-treated rats and 2.5 ± 0.3 (n = 5) in controls (Student's t
Comment
Chronic ethanol consumption significantly increased noradrenergic nerve-mediated contractions of CSM in response to EFS. This observation corroborates previous findings, namely, that treatment of rabbits for 6 weeks with an ethanol solution of 5% vol/vol induced increased responses of the CSM to EFS.10 Surprisingly, the contraction induced by phenylephrine—a selective α1 agonist—was not affected by chronic ethanol consumption in our model. Similar results were previously described in the CSM
Conclusions
Despite the overexpression of eNOS and iNOS in ethanol-treated rats, the impaired relaxation induced by acetylcholine may suggest that chronic ethanol consumption induces endothelial dysfunction.
Acknowledgments
We thank Sonia Dreossi for technical support. We also thank Professor Margaret de Castro for testosterone measurements.
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2017, European Journal of PharmacologyCitation Excerpt :The erectile response was calculated using the maximum ICP response normalized to MAP at the time of maximum ICP. The CSM was isolated and placed in 5-ml organ chamber containing Krebs solution at 37 °C as previously described (Lizarte et al., 2009). The strips of CSM were stretched to a resting tension of 3 mN and allowed to equilibrate for 60 min.
This work was supported by CAPES (Coordenação de Aperfeiçoamento de Pessoal de Nível Superior).