Erectile Dysfunction in Young Non-Obese Type II Diabetic Goto-Kakizaki Rats is Associated with Decreased eNOS Phosphorylation at Ser1177

Introduction. Diabetes mellitus (DM) is a risk factor for erectile dysfunction (ED). Although type 2 DM is responsible for 90-95% diabetes cases, type 1 DM experimental models are commonly used to study diabetes-associated ED. Aim. Goto-Kakizaki (GK) rat model is relevant to ED studies since the great majority of patients with type 2 diabetes display mild deficits in glucose-stimulated insulin secretion, insulin resistance, and hyperglycemia. We hypothesized that GK rats display ED which is associated with decreased nitric oxide (NO) bioavailability. Methods. Wistar and GK rats were used at 10 and 18 weeks of age. Changes in the ratio of intracavernosal pressure/mean arterial pressure (ICP/MAP) after electrical stimulation of cavernosal nerve were determined in vivo. Cavernosal contractility was induced by electrical field stimulation (EFS) and phenylephrine (PE). In addition, nonadrenergic-noncholinergic (NANC)- and sodium nitroprusside (SNP)-induced relaxation were determined. Cavernosal neuronal nitric oxide synthase (nNOS) and endothelial nitric oxide synthase (eNOS) mRNA and protein expression were also measured. Main Outcome Measure. GK diabetic rats display ED associated with decreased cavernosal expression of eNOS protein. Results. GK rats at 10 and 18 weeks demonstrated impaired erectile function represented by decreased ICP/MAP responses. Ten-week-old GK animals displayed increased PE responses and no changes in EFS-induced contraction. Conversely, contractile responses to EFS and PE were decreased in cavernosal tissue from GK rats at 18 weeks of age. Moreover, GK rats at 18 weeks of age displayed increased NANC-mediated relaxation, but not to SNP. In addition, ED was associated with decreased eNOS protein expression at both ages. Conclusion. Although GK rats display ED, they exhibit changes in cavernosal reactivity that would facilitate erectile responses. These results are in contrast to those described in other experimental diabetes models. This may be due to compensatory mechanisms in cavernosal tissue to overcome restricted pre-penile arterial blood supply or impaired veno-occlusive mechanisms. Carneiro FS, Giachini FRC, Carneiro ZN, Lima VV, Ergul A, Webb RC, and Tostes RC. Erectile dysfunction in young non-obese type II diabetic Goto-Kakizaki rats is associated with decreased eNOS phosphorylation at Ser1177. J Sex Med 2010;7:3620-3634.

Headache and Symptoms of Temporomandibular Disorder: An Epidemiological Study

Objectives.-A population-based cross-sectional study was conducted to estimate the prevalence of migraine, episodic tension-type headaches (ETTH), and chronic daily headaches (CDH), as well as the presence of symptoms of temporomandibular disorders (TMD) in the adult population. Background.-The potential comorbidity of headache syndromes and TMD has been established mostly based on clinic-based studies. Methods.-A representative sample of 1230 inhabitants (51.5% women) was interviewed by a validated phone survey. TMD symptoms were assessed through 5 questions, as recommended by the American Academy of Orofacial Pain, in an attempt to classify possible TMD. Primary headaches were diagnosed based on the International Classification of Headache Disorders. Results.-When at least 1 TMD symptom was reported, any headache happened in 56.5% vs 31.9% (P < .0001) in those with no symptoms. For 2 symptoms, figures were 65.1% vs 36.3% (P < .0001); for 3 or more symptoms, the difference was even more pronounced: 72.8% vs 37.9%. (P < .0001). Taking individuals without headache as the reference, the prevalence of at least 1 TMD symptom was increased in ETTH (prevalence ratio = 1.48, 95% confidence interval = 1.20-1.79), migraine (2.10, 1.80-2.47) and CDH (2.41, 1.84-3.17). At least 2 TMD symptoms also happened more frequently in migraine (4.4, 3.0-6.3), CDH (3.4; 1.5-7.6), and ETTH (2.1; 1.3-3.2), relative to individuals with no headaches. Finally, 3 or more TMD symptoms were also more common in migraine (6.2; 3.8-10.2) than in no headaches. Differences were significant for ETTH (2.7 1.5-4.8), and were numerically but not significant for CDH (2.3; 0.66-8.04). Conclusions.-Temporomandibular disorder symptoms are more common in migraine, ETTH, and CDH relative to individuals without headache. Magnitude of association is higher for migraine. Future studies should clarify the nature of the relationship.

Temporomandibular Disorders Are Differentially Associated With Headache Diagnoses A Controlled Study

Objectives: Temporomandibular disorders (TMDs) are considered to be comorbid with headaches. Earlier population studies have suggested that TMD may also be a risk factor for migraine progression. If that is true, TMD should be associated with specific headache syndromes (eg, migraine and chronic migraine), but not with headaches overall. Accordingly, our aim was to explore the relationship between TMD subtypes and severity with primary headaches in a controlled clinical study. Methods: The sample consisted of 300 individuals. TMDs were assessed using the Research Diagnostic Criteria for TMD, and primary headache was classified according to International Classification for Headache Disorders-2. Univariate and multivariate models assessed headache diagnoses and frequency as a function of the parameters of TMD. Results: Relative to those without TMD, individuals with myofascial TMD were significantly more likely to have chronic daily headaches (CDHs) [ relative risk (RR) = 7.8; 95% confidence interval (CI), 3.1-19.6], migraine (RR = 4.4; 95% CI, 1.7-11.7), and episodic tension-type headache (RR = 4.4; 95% CI, 1.5-12.6). Grade of TMD pain was associated with increased odds of CDH (P < 0.0001), migraine (P < 0.0001), and episodic tension-type headache (P < 0.05). TMD severity was also associated with headache frequency. In multivariate analyses, TMD was associated with migraine and CDH (P = 0.001). Painful TMD (P = 0.0034) and grade of TMD pain (P < 0.001) were associated with headache frequency. Discussion: TMD, TMD subtypes, and TMD severity are independently associated with specific headache syndromes and with headache frequency. This differential association suggests that the presence of central facilitation of nociceptive inputs may be of importance, as positive association was observed only when muscular TMD pain was involved.