Related Experiment Video
Updated: May 30, 2026
08:21
Effects of Blast-induced Neurotrauma on Pressurized Rodent Middle Cerebral Arteries
Published on: April 1, 2019
Pericyte-mediated vasoconstriction underlies TBI-induced hypoperfusion.
Paula Dore-Duffy1, Sherry Wang, Afroza Mehedi
1Department of Neurology, Wayne State University School of Medicine, Detroit, MI 48201, USA. pdduffy@med.wayne.edu
Neurological Research
|August 2, 2011
Summary
Traumatic brain injury (TBI) increases endothelin-1 signaling in pericytes, leading to reduced blood flow. Blocking endothelin-A receptors (ETrA) with antagonists reduces pericyte activation and improves microvascular diameter after TBI.
Area of Science:
- Neuroscience
- Vascular Biology
- Trauma Research
Background:
- Endothelin-1 (ET-1) and its receptors (ETRA, ET RB) are implicated in traumatic brain injury (TBI)-induced cerebral vasospasm, oxidative stress, and hypoperfusion.
- ET-1's role in TBI-induced hypoperfusion is primarily linked to ETRA activation, but the precise mechanism remains unclear.
- Microvascular pericytes are investigated for their potential role in ET-1-mediated TBI pathophysiology.
Purpose of the Study:
- To investigate the role of microvascular pericytes in endothelin-1-mediated pathophysiology following traumatic brain injury (TBI).
- To examine pericyte expression of ET-1 and its receptors (ETRA, ET RB) in primary culture and in rat brains post-TBI.
- To assess the effect of ETRA antagonists on pericyte activation and microvascular changes after TBI.
Main Methods:
- Primary pericyte cultures and rat brain tissue (sham and TBI) were analyzed for ET-1, ETRA, and ET RB expression.
- Adult male rats underwent TBI using a closed head acceleration impact model.
- Rats received intracerebroventricular injections of the ETRA antagonist BQ-123 prior to TBI induction.
Main Results:
- Primary pericytes express both ET-1 and its receptors, ETRA and ET RB.
- TBI significantly increased alpha-smooth muscle actin (SMA)-positive pericytes in microvessels within 4 hours, correlating with reduced arteriolar and capillary diameter.
- Increased ET-1, ETRA, and ET RB expression was observed in capillaries post-TBI, with ETRA antagonist treatment decreasing pericyte activation and normalizing microvascular diameter.
Conclusions:
- Pericyte-mediated regulation of microvessel blood flow, induced by ET-1, may contribute to decreased vasoconstriction following TBI.
- ETRA antagonists show potential in ameliorating TBI-induced hypoperfusion by inhibiting ET-1-mediated alpha-SMA upregulation in pericytes.
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