Mice Models for Peripheral Denervation to Enhance Vascular Regeneration.

Abstract

Sympathetic innervation plays a critical role in regulating vascular function, yet its influence on vascular regeneration and reinnervation following ischemic injury remains poorly understood. This study develops and validates murine models of localized sympathetic denervation using 6-hydroxydopamine (6-OHDA) to enable study of the sympathetic nervous system's impact on vascular systems during tissue repair. Two methods of 6-OHDA administration were employed: a single topical application during open surgery and minimally invasive weekly subcutaneous injections. The topical application model achieved temporary denervation lasting 1 week without causing vascular damage, while the subcutaneous injection model provided sustained denervation for up to 4 weeks with minimal inflammation and no significant changes to vascular architecture. To investigate the effects of denervation in an ischemic context, these models were combined with a hindlimb ischemia model. Ischemia induced persistent denervation in both 6-OHDA-treated and control limbs, with limited sympathetic nerve regeneration observed over 4 weeks. Despite persistent denervation, microvascular density and perfusion recovery in ischemic muscles were comparable between denervated and control groups. This suggests that ischemia governs vascular regeneration independently of sympathetic input. These results demonstrate that localized 6-OHDA administration provides a versatile tool for achieving controlled sympathetic denervation in peripheral arteries. These models provide a novel platform for studying vascular regeneration and reinnervation under both normal and ischemic conditions, offering novel insights into the interactions between neural regulation and vascular repair processes. This work lays the foundation for future research into neural-vascular crosstalk and new possibilities for developing regenerative therapies targeting the autonomic regulation of vascular health.