Abstract | BACKGROUND: The hormone and neuropeptide arginine-vasopressin is designated to the maintenance of osmotic homoeostasis and blood pressure regulation. While experimental data show vasopressin V(1A) receptors to regulate aquaporin (AQP)4 water channel dependent brain water movement, the specific role in vasogenic and cytotoxic edema formation remains unclear. The present study was designed to quantify the V(1A) receptor mediated regional brain edema formation in two clinically relevant experimental models, brain injury combined with secondary insult and focal ischemia. METHODS: Male Sprague-Dawley rats were randomly assigned to a continuous infusion of vehicle (1 % DMSO) or the selective non- peptide V(1A) antagonist SR49059 (83nM = 1 mg/kg) starting before controlled cortical impact (CCI) injury plus hypoxia and hypotension (HH, 30 min), or middle cerebral artery (MCA) occlusion (2 h + 2 h reperfusion). RESULTS: A global analysis of brain water content by the wet/dry weight method allowed optimizing the SR49059 dosage, and demonstrated the down-regulation of brain AQP4 expression by immunoblotting. Microgravimetrical quantification in 64 one mm(3) samples per animal (n = 6 per group) from bregma +2.7 to -6.3 mm analysis demonstrated brain edema to be reduced at 4 h by SR49059 treatment in the injured and contralateral cortex following CCI + HH (p = 0.007, p < 0.001) and in the infarct area following MCA occlusion (p = 0.013, p = 0.002, p = 0.004). CONCLUSIONS:
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Authors | Andrea Kleindienst, Jana G Dunbar, Renee Glisson, Anthony Marmarou |
Journal | Acta neurochirurgica
(Acta Neurochir (Wien))
Vol. 155
Issue 1
Pg. 151-64
(Jan 2013)
ISSN: 0942-0940 [Electronic] Austria |
PMID | 23188468
(Publication Type: Journal Article, Research Support, N.I.H., Extramural)
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Chemical References |
- Antidiuretic Hormone Receptor Antagonists
- Aquaporin 4
- Hormone Antagonists
- Indoles
- Pyrrolidines
- Receptors, Vasopressin
- relcovaptan
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Topics |
- Animals
- Antidiuretic Hormone Receptor Antagonists
- Aquaporin 4
(metabolism)
- Brain Edema
(etiology, metabolism, pathology)
- Brain Injuries
(complications, metabolism, pathology)
- Disease Models, Animal
- Hormone Antagonists
(pharmacology)
- Indoles
(pharmacology)
- Infarction, Middle Cerebral Artery
(complications, metabolism, pathology)
- Male
- Pyrrolidines
(pharmacology)
- Rats
- Rats, Sprague-Dawley
- Receptors, Vasopressin
(physiology)
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