Related Experiment Video
Updated: Jun 26, 2026
An In Vivo Duo-color Method for Imaging Vascular Dynamics Following Contusive Spinal Cord Injury
Published on: December 31, 2017
De novo expression of Trpm4 initiates secondary hemorrhage in spinal cord injury
Volodymyr Gerzanich1, S Kyoon Woo, Rudi Vennekens
1Department of Neurosurgery, University of Maryland School of Medicine, 22 South Greene Street, Suite S12D, Baltimore, Maryland 21201-1595, USA.
Abstract:
The role of transient receptor potential M4 (Trpm4), an unusual member of the Trp family of ion channels, is poorly understood. Using rodent models of spinal cord injury, we studied involvement of Trpm4 in the progressive expansion of secondary hemorrhage associated with capillary fragmentation, the most destructive mechanism of secondary injury in the central nervous system. Trpm4 mRNA and protein were abundantly upregulated in capillaries preceding their fragmentation and formation of petechial hemorrhages. Trpm4 expression in vitro rendered COS-7 cells highly susceptible to oncotic swelling and oncotic death following ATP depletion. After spinal cord injury, in vivo gene suppression in rats treated with Trpm4 antisense or in Trpm4(-/-) mice preserved capillary structural integrity, eliminated secondary hemorrhage, yielded a threefold to fivefold reduction in lesion volume and produced a substantial improvement in neurological function. To our knowledge, this is the first example of a Trp channel that must undergo de novo expression for manifestation of central nervous system pathology.
Insights
Transient Receptor Potential M4 (Trpm4) channels are upregulated after spinal cord injury, contributing to capillary damage and lesion expansion. Inhibiting Trpm4 preserves capillaries, reduces lesion size, and improves neurological function.
Area of Science:
- Neuroscience
- Physiology
- Molecular Biology
Background:
- The role of Transient Receptor Potential M4 (Trpm4) ion channels in central nervous system pathology is largely unknown.
- Spinal cord injury (SCI) involves progressive secondary injury mechanisms, including capillary fragmentation and hemorrhage, which exacerbate damage.
Purpose of the Study:
- To investigate the involvement of Trpm4 in secondary hemorrhage and lesion expansion following SCI.
- To determine if Trpm4 de novo expression is critical for SCI-induced pathology.
Main Methods:
- Utilized rodent models of SCI.
- Examined Trpm4 mRNA and protein expression in capillaries.
- Investigated Trpm4's role in capillary integrity and cell death in vitro.
- Assessed the effects of Trpm4 gene suppression (antisense or knockout) on SCI outcomes in vivo.
Main Results:
- Trpm4 was significantly upregulated in capillaries preceding fragmentation and hemorrhage post-SCI.
- In vitro, Trpm4 expression increased susceptibility to oncotic swelling and cell death.
- Trpm4 suppression in vivo preserved capillary integrity, abolished secondary hemorrhage, and reduced lesion volume (3-5 fold).
- Neurological function was substantially improved in Trpm4-suppressed models.
Conclusions:
- Trpm4 plays a critical role in the pathogenesis of secondary injury after SCI.
- De novo expression of Trpm4 is essential for SCI-induced capillary pathology and subsequent neurological deficits.
- Trpm4 represents a potential therapeutic target for mitigating SCI outcomes.
Related Concept Videos
01:25Secondary Spinal Cord Injury llI: Pathophysiology
01:14Spinal Cord Injury ll: Pathophysiology
01:29Hemorrhagic Stroke ll: Pathophysiology