Multidimensional Evaluation of Vascular Dysfunction in Diabetic Erectile Dysfunction: Synergistic Application of ICP Measurement, Laser Speckle Blood Perfusion Imaging, and Ex Vivo Microvascular Tension Measurement.

Diabetic erectile dysfunction (DMED) is a complex condition primarily characterized by impaired vasodilation and inadequate blood perfusion. As of 2023, the available techniques for evaluating vascular function are limited. Intracavernous pressure (ICP) measurement is regarded as the gold standard for assessing erectile function in animals, yet this approach struggles to differentiate between vascular endothelial dysfunction and smooth muscle dysfunction. This study assessed erectile function in DMED rats and analyzed the hemorheology of the penile corpus cavernosum in conjunction with laser speckle blood perfusion imaging (LSBPI). The vasomotor function of the internal iliac artery (IIA) was evaluated using ex vivo microvascular tension measurement. Masson staining was applied to investigate structural alterations in the IIA and cavernous arteries, and immunofluorescence was utilized to measure the protein expression levels of vascular cell adhesion molecule (VCAM), vascular endothelial growth factor (VEGF), and endothelial nitric oxide synthase (eNOS), revealing vascular functional status at both tissue and molecular levels. The model group showed lower ICP values, diminished blood flow, and reduced vasoconstrictive capacity compared to the control group. High-potassium stimulation caused a more pronounced decrease in vascular tension in the model group. Sodium nitroprusside produced comparable vasodilatory responses in both groups; following incubation with N-nitro-L-arginine methyl ester, the model group demonstrated decreased vascular tension. The model group exhibited fibrosis in penile tissue, elevated levels of VCAM-1 and VEGF, and decreased expression of eNOS protein. The integration of ICP with LSBPI and vascular tensiometry enables simultaneous in vivo hemodynamic monitoring and ex vivo functional dissection of endothelial-smooth muscle interactions in DMED.