Dose-dependent effect of 2APB on delayed cerebral vasospasm after experimental subarachnoid hemorrhage in rats

Objective: Cerebral vasospasm is one of the most impactful complications affecting mortality and morbidity in patients with subarachnoid hemorrhage. Due to the incomplete understanding of its pathophysiology, prevention, and treatment, it poses a significant challenge in the practice of neurosurgery. This study comparatively assesses the dose-dependent effect of 2-Aminoethoxydiphenyl borate (2APB), which has been investigated and found significant in the early stage, on delayed cerebral vasospasm. Materials and Methods: This experimental study was conducted on 60 adult male Wistar rats weighing between 300-350 grams. A single hemorrhage model was used to induce subarachnoid hemorrhage. The rats were divided into four groups: 1. Control Group, 2. Sham Group, 3. 2-APB 0.5mg/kg Group, and 4. 2-APB 2mg/kg Group. The drugs were administered intraperitoneally once a day for five days. At the end of the fifth day, the rats were sacrificed. Histopathologically, the diameter and wall thickness of the basilar artery were measured and biochemically, the levels of TAS (total antioxidant situation) and TOS (total oxidant situation) were evaluated in rat serum. Results: The dose-dependent effects of 2-APB on arterial diameter, wall thickness, VEGF H-Score (vascular endothelial growth factor), TOS, TAS and OSI (oxidative stress index) parameters were evaluated in rats with subarachnoid hemorrhage and it was found that 2-APB had statistically positive effects on vasospasm but had no significant effect on oxidative stress factors. Conclusion: This study demonstrated that 2-APB may be effective in the prevention and treatment of vasospasm following subarachnoid hemorrhage. However, further experimental and clinical studies are needed before 2-APB can be used clinically. Key Words: Subarachnoid hemorrhage, cerebral vasospasm, calcium channel blocker, 2-APB.