Association Study of the β2-Adrenergic Receptor Gene Polymorphisms and Hypertension in the Northern Han Chinese

Background: The beta 2-adrenergic receptor (ADRB2) gene has been widely researched as a candidate gene for essential hypertension (EH), but no consensus has been reached in different ethnicities. The aim of the present study was to evaluate the possible association between the ADRB2 gene polymorphisms and the EH risk in the Northern Han Chinese population. Methodology/Principal Findings: This study included 747 hypertensive subjects and 390 healthy volunteers as control subjects in the Northern Han Chinese. Genotyping was performed to identify the C-47T, A46G and C79G polymorphisms of the ADRB2 gene. G allelic frequency of A46G polymorphism was significantly higher in hypertensive subjects (P = 0.011, OR = 1.287, 95% CI [1.059-1.565]) than that in controls. Significant association could also be found in dominant genetic model (GG+AG vs. AA, P = 0.006, OR = 1.497, 95% CI [1.121-1.998]), in homozygote comparison (GG vs. AA, P = 0.025, OR = 1.568, 95% CI [1.059-2.322]), and in additive genetic model (GG vs. AG vs. AA, P = 0.012, OR = 1.282, 95% CI [1.056-1.555]). Subgroup analyses performed by gender suggested that this association could be found in male, but not in female. Stratification analyses by obesity showed that A46G polymorphism was related to the prevalence of hypertension in the obese population (GG vs. AG vs. AA, P<0.001, OR = 1.645, 95% CI [1.258-2.151]). Significant interaction was found between A46G genotypes and body mass index on EH risk. No significant association could be found between C-47T or C79G polymorphism and EH risk. Linkage disequilibrium was detected between the C-47T, A46G and C79G polymorphisms. Haplotype analyses observed that the T-47-A46-C79 haplotype was a protective haplotype for EH, while the T-47-G46-C79 haplotype increased the risk. Conclusions/Significances: We revealed that the ADRB2 A46G polymorphism might increase the risk for EH in the Northern Han Chinese population.Multidisciplinary SciencesSCI(E)7ARTICLE4null

Autonomic cerebral vascular response to sildenafil in diabetic patient

<p>Abstract</p> <p>Background</p> <p>Erectile dysfunction is a common problem in type 2 diabetic patients who are at higher risk of cerebrovascular events, and it's recorded with sildenafil, a drug which is primarily used for erectile dysfunction.</p> <p>Objectives</p> <p>We tested the hypothesis whether or not sildenafil modulates cerebrovascular reactivity (CVR) in patients with type 2 diabetes mellitus.</p> <p>Methods</p> <p>A total of 35 male participants were enrolled; eighteen with type 2 diabetes mellitus matched with seventeen normal individuals. Transcranial Doppler Ultrasonographic examination (TCD) was performed for all participants to insonate the middle cerebral artery (MCA) through a trans-temporal window. CVR was assessed by using breath holding (BH)-hyperventilation (HV) test, before and after oral 50 mg sildenafil; recordings were analyzed by using SPSS program version 12.</p> <p>Results</p> <p>In normal individuals, sildenafil did not result in statistically significant change in breath holding index (BHI) from 0.91 ± 0.11 to 0.81 ± 0.09 and full range of vasodilatation (FVD) from (59.4% ± 6.3%) to (53.7% ± 4.9%). In diabetic patients, giving sildenafil resulted in significant increase in BHI (from 0.74 ± 0.14 to 1.03 ± 0.14) and FVD (from 60.2% ± 4.96% to 74% ± 4.8%), (p < 0.05).</p> <p>Conclusion</p> <p>Sildenafil significantly improves CVR in type 2 diabetic patients but not in normal subjects.</p