An interventional system that utilizes a carotid chemoreceptor(s) and optionally baroreceptor(s) for inducing vasodilatation in blood vessels of the brain is provided for treating ischemic conditions of the CNS, such as ischemic stroke and cerebral vasospasm. The system includes an electrical signal generator and an endovascular module with electrode units for transiently being disposed in the internal and external carotid arteries, adjacent a carotid body.