Trigeminal Nerve Stimulation Improves Cerebral Macrocirculation and Microcirculation After Subarachnoid Hemorrhage:...

Area of Science:

• Neuroscience
• Cerebrovascular Medicine
• Surgical Innovation

Background:

• Delayed cerebral ischemia (DCI) is a major complication after aneurysmal subarachnoid hemorrhage (SAH), driven by vasospasm and microcirculatory issues.
• Current treatments for DCI are insufficient, highlighting the need for novel therapeutic strategies.
• The trigeminal nerve's role in regulating cerebral blood flow presents a potential target for intervention.

Purpose of the Study:

• To investigate the efficacy of electrical trigeminal nerve stimulation (TNS) in restoring cerebral macrocirculation and microcirculation.
• To evaluate TNS's impact on mitigating the secondary insults following experimental subarachnoid hemorrhage (SAH) in rats.

Main Methods:

• Rats underwent SAH induction, followed by KCl-induced cortical spreading depolarization.
• The SAH-TNS group received electrical trigeminal nerve stimulation, while controls did not.
• Key outcomes assessed included cerebral vasospasm, microvascular changes, inflammatory markers, ischemia, apoptosis, and neurobehavioral function.

Main Results:

• TNS significantly increased the diameter of major cerebral arteries and reduced arteriolar wall thickness in SAH rats.
• TNS treatment decreased markers of inflammation (ICAM-1) and microthrombi formation.
• TNS ameliorated ischemic injury, reduced cellular apoptosis, and improved neurobehavioral deficits in the SAH model.

Conclusions:

• Electrical trigeminal nerve stimulation effectively enhances cerebral circulation at both macro and microcirculatory levels.
• TNS demonstrates a therapeutic potential to mitigate cerebral ischemia and its consequences post-SAH.
• TNS represents a promising strategy for managing delayed cerebral ischemia following subarachnoid hemorrhage.