The Effects of Urapidil as an Alpha Receptor Blocker on Spinal Cord Ichemia-Reperfusion Injury in Male Rats

Background : The aim of this experimental study was to evaluate the potential protective effects of urapidil (URA) on spinal cord ischemia-reperfusion (IR) injury in a rat model. Twenty-four adult male Wistar Albino rats (250 ± 20 g) were randomly divided into four groups (n = 6 each): Control (CR), Sham (SH), Ischemia-Reperfusion (IR), and Ischemia-Reperfusion + URA (IR+URA). Anesthesia was achieved with xylazine (13 mg/kg i.m.) and ketamine (10% i.m.). The IR and IR+URA groups underwent infrarenal abdominal aorta clamping for 30 minutes followed by reperfusion. URA was administered intraperitoneally at 0.5 mg/kg one hour before surgery and 5 mg/kg after reperfusion. Motor function was evaluated at 24 h using the Tarlov score. Biochemical parameters (NO, GPx, TNFα, IL6, MDA, NGF, IL1β) were measured in blood samples. Spinal cord(L4–L6)histology (H&E, toluidineblue) andimmunohistochemistry (eNOS, Caspase3, TNFα, IL1β, IL6, MMP9) were assessed. One-way ANOVA and Dun- can’s test were used (p < 0.05). Results : The IR group had significantly lower Tarlov scores compared with other 1groups (p < 0.001). The IR+URA group showed no statistical difference in motor scores compared to CR and SH groups. GPx values were significantly higher in IR+URA than all other groups (p = 0.001). TNFα and IL1β were significantly elevated in IR vs CR (p < 0.05) and were significantly reduced in IR+URA vs IR (p < 0.05). Histopathologically and immunohistochemically, IR induced significant neuronal degeneration, glial proliferation, increased eNOS, Caspase3, TNFα, IL1β, IL6 and MMP9 immunoreactivity; these changes regressed with URA. Conclusion : Urapidil demonstrated a neuroprotective effect in spinal cord IR injury by preserving motor function, enhancing antioxidant defense and reducing inflammation. These findings suggest URA as a promising candidate for preventing spinal cord ischemia-reperfusion injury in aortic surgery, subject to further investigation.