Cystathionine γ Lyase Deletion Enhances Corpus Cavernosum Contraction via Thromboxane A

Cystathionine γ-lyase (CSE) produces hydrogen sulfide (H₂S), a vasodilator critical for vascular function. While its systemic effects are well-documented, its role in erectile physiology remains unclear. This study investigated the impact of CSE deletion on vascular and erectile tissue reactivity. We hypothesized that CSE knockout (CSE-KO) mice would exhibit endothelial dysfunction. A total of 22 CSE-KO and 22 age-matched wild-type (WT) controls were studied at one year of age. The internal iliac artery (IIA), internal pudendal artery (IPA), and corpus cavernosum (CC) were harvested for NEW & NOTEWORTHY: This study highlights the critical role of hydrogen sulfide (H₂S) in erectile physiology by demonstrating that CSE deletion does not impair endothelial function but significantly enhances neurogenic and thromboxane A2 receptor-induced vasoconstriction specifically in the corpus cavernosum (CC). These findings suggest that endogenous H₂S modulates neurovascular control of erection. Its deficiency predisposes the erectile system to heightened vascular resistance predominantly in the end organ, providing novel insights into the vascular mechanisms underlying erectile dysfunction.