Selective Vasopressin-1a receptor antagonist prevents brain edema, reduces astrocytic cell swelling and GFAP, V1aR and AQP4 expression after focal traumatic brain injury
| Autor: | Christina R. Marmarou, Aristotelis S. Filippidis, Xiuyin Liang, Clive M. Baumgarten, Naqeeb H. Abidi, Keisuke Taya, Shanaz Parveen, Scott C. Henderson, Harold F. Young |
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| Jazyk: | angličtina |
| Rok vydání: | 2014 |
| Předmět: |
Male
medicine.medical_specialty Vasopressin Receptors Vasopressin Indoles Pyrrolidines medicine.drug_class Traumatic brain injury Gene Expression Brain Edema Article Rats Sprague-Dawley Random Allocation Internal medicine Edema Glial Fibrillary Acidic Protein medicine Animals Receptor Molecular Biology Aquaporin 4 Microscopy Confocal Glial fibrillary acidic protein biology business.industry General Neuroscience Receptor antagonist medicine.disease Immunohistochemistry Rats Disease Models Animal Endocrinology medicine.anatomical_structure Neuroprotective Agents Anesthesia Astrocytes Brain Injuries biology.protein Neurology (clinical) medicine.symptom business Antidiuretic Hormone Receptor Antagonists Developmental Biology Astrocyte |
| Popis: | A secondary and often lethal consequence of traumatic brain injury is cellular edema that we posit is due to astrocytic swelling caused by transmembrane water fluxes augmented by vasopressin-regulated aquaporin-4 (AQP4). We therefore tested whether vasopressin 1a receptor (V1aR) inhibition would suppress astrocyte AQP4, reduce astrocytic edema, and thereby diminish TBI-induced edematous changes. V1aR inhibition by SR49059 significantly reduced brain edema after cortical contusion injury (CCI) in rat 5h post-injury. Injured-hemisphere brain water content (n=6 animals/group) and astrocytic area (n=3/group) were significantly higher in CCI-vehicle (80.5±0.3%; 18.0±1.4 µm(2)) versus sham groups (78.3±0.1%; 9.5±0.9 µm(2)), and SR49059 blunted CCI-induced increases in brain edema (79.0±0.2%; 9.4±0.8µm(2)). CCI significantly up-regulated GFAP, V1aR and AQP4 protein levels and SR49059 suppressed injury induced up regulation (n=6/group). In CCI-vehicle, sham and CCI-SR49059 groups, GFAP was 1.58±0.04, 0.47±0.02, and 0.81±0.03, respectively; V1aR was 1.00±0.06, 0.45±0.05, and 0.46±0.09; and AQP4 was 2.03±0.34, 0.49±0.04, and 0.92±0.22. Confocal immunohistochemistry gave analogous results. In CCI-vehicle, sham and CCI-SR49059 groups, fluorescence intensity of GFAP was 349±38, 56±5, and 244±30, respectively, V1aR was 601±71, 117.8±14, and 390±76, and AQP4 was 818±117, 158±5, and 458±55 (n=3/group). The results support that edema was predominantly cellular following CCI and documented that V1aR inhibition with SR49059 suppressed injury-induced up regulation of GFAP, V1A and AQP4, blunting edematous changes. Our findings suggest V1aR inhibitors may be potential therapeutic tools to prevent cellular swelling and provide treatment for post-traumatic brain edema. |
| Databáze: | OpenAIRE |
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