Avaliação dos efeitos da hiperglicemia sobre a estrutura vascular peniana em coelhos Nova Zelândia

Abstract

Patients with diabetes mellitus (DM) have a high incidence of erectile dysfunction (ED). Several epidemiological studies have assessed the correlation between DM and ED. Evaluation of animal models demonstrated that neural and vascular changes seen with DM may be associated with ED. Vascular diseases such as microangiopathy, atherosclerosis, and hypertension are often observed in patients with DM. The aim of this study was to assess the morphological changes of penile vascular structures and the corpus cavernosum area in alloxan-induced diabetic rabbits. Twenty male rabbits (2 months old) were divided into two groups with 10 rabbits each, the control group (CG) and the diabetic group (DG). The animals from the DG received an intravenous injection of alloxan (100mg/kg) to induce DM. Ten weeks after the induction of DM, all animals were euthanized. Two fragments of the penile shaft were harvested and samples were processed and paraffin embedded. Sections (5m) were cut and stained for histological and immunohistochemical markers. Nuclear protrusion toward the lumen, and cytoplasmic vacuolization were observed in the tunica intima of the dorsal artery of the penis in DG. The thicknesses of the tunica media increased significantly from 35.01±3,17 µm in DG to 44.33±8,43 µm in DG (p=0,0350). Was also observed a significant increase in the area of the tunica media (p=0,0179). There was no significant change in smooth muscle cell density in the tunica media of the dorsal artery of the penis (p=0,0855). The collagen fiber pattern of the tunica adventitia of the dorsal artery of the penis was different between the control and diabetic groups. There was a decrease of 37% in the area occupied by the cavernous sinuses in DG, and the difference between CG and DG was significant (p = 0.0013). Alloxan-induced DM in rabbits promotes important changes in penile vascular structures, thereby decreasing blood supply and affecting penile hemodynamics, leading to erectile dysfunction