Assessment of the relationship between asymmetric dimethylarginine and severity of erectile dysfunction and coronary artery disease.

The plasma concentration of asymmetrical dimethylarginine (ADMA), an inhibitor of nitric oxide synthase, has been linked to endothelial dysfunction. We investigated the relation between plasma ADMA concentration and severity of erectile dysfunction (ED) and coronary artery disease (CAD). We measured plasma levels of ADMA in 92 male patients. Patients were divided into three groups: group 1 (n = 41), patients with ED and without CAD; group 2 (n = 29), patients with stable CAD; group 3 (n = 22), control group (patients without CAD or ED). Erectile function was evaluated by the erectile function domain of the international index of erectile function (IIEF-EFD) a validated 15-item self-administered questionnaire. Erectile function is specifically addressed by six questions that form the so-called erectile function domain of the questionnaire. Each question is scored 0-5. ED is defined as any value < 26. Patients with CAD who have stable angina pectoris were selected after coronary angiography. ADMA was analyzed by ELISA method. Group 1 had significantly higher concentrations of plasma ADMA than groups 2 and 3 (respectively, 0.75 ± 0.40 vs. 0.50 ± 0.30, P = 0.013; 0.75 ± 0.40 vs. 0.50 ± 0.25, P = 0.021). There was negative correlation between ADMA and IIEF-EFD score in all groups (n = 92) (r = -0.322, P = 0.002). In a multiple logistic regression analysis adjusting for age, hyperlipidemia, ADMA remained independent predictor for severe ED. Odds ratio for plasma ADMA was 14.151 (1.101-181.940; P = 0.042). First of all, this study provides that ADMA concentrations are significantly higher in patients who have ED when compared to patients with CAD and controls. Second, there was a negative correlation between ADMA and severity of ED. Elevating levels of circulating ADMA is an independent risk factor for severe of ED, and ADMA may be a link between CAD and ED.

Histopathological and scintigraphic comparisons of the protective effects of L-carnitine and amifostine against radiation-induced late renal toxicity in rats.

1. The aim of the present study was to compare the protective effects of L-carnitine and amifostine against radiation-induced late nephrotoxicity using technetium-99m diethylenetriaminepentaacetic acid scintigraphy and histopathological examination. 2. Seventy-one Albino rats were randomly divided into six groups as follows: (i) AMI + RAD (n = 15), 200 mg/kg, i.p., amifostine 30 min prior to irradiation (a single dose of 9 Gy); (ii) LC + RAD (n = 15), 300 mg/kg, i.p., L-carnitine 30 min prior to irradiation; (iii) LC (n = 10), 300 mg/kg, i.p., L-carnitine 30 min prior to sham irradiation; (iv) AMI (n = 10), 200 mg/kg, i.p., amifostine 30 min prior to sham irradiation; RAD (n = 11), 1 mL/kg, i.p., normal saline 30 min prior to irradiation; and (vi) control (n = 10), 1 mL/kg, i.p., normal saline 30 min prior to sham irradiation. Scintigraphy was performed before treatment and again 6 months after treatment. Kidneys were examined by light microscopy and a histopathological scoring system was used to assess the degree of renal damage. 3. The main histopathological findings were proximal tubular damage and interstitial fibrosis. Glomerular injury was similar in all groups. Tubular degeneration and atrophy were less common in the AMI + RAD group than in the RAD group (P = 0.011 and P = 0.015, respectively), as well as in the LC + RAD group compared with the RAD group (P = 0.028 and P = 0.036, respectively). Interstitial fibrosis in the AMI + RAD and LC + RAD groups was significantly less than that in the RAD group (P = 0.015 and P = 0.015, respectively). The highest total renal injury score (9) was seen in the RAD group. On scintigraphy, there were significant differences in post-treatment time to peak count (T(max)) and time from peak count to half count (T((1/2))) values (P = 0.01 and 0.02, respectively) between groups in the right kidney. In the control and RAD groups, the T((1/2)) of the right kidney was 8 +/- 2 and 21 +/- 2 min, respectively. The T(max) values for the AMI + RAD and LC + RAD groups (2.8 +/- 0.2 and 3.2 +/- 0.2 min, respectively) were similar to those in the control group (2.5 +/- 0.3 min). 4. Based on the results of the present study, L-carnitine and amifostine have comparable and significant protective effects against radiation-induced late nephrotoxicity.