The change of gamma-aminobutyric acid A receptorα1 subunit mRNA expression in nitroglycerin induced migraine rat model

Abstract

Objective To investigate the change of gamma-aminobutyric acid A (GABAA) receptor α1 subunit mRNA expression in nitroglycerin induced migraine rat model，thus suggesting the relationship between GABAA receptor and migraine. Methods Thirty adult female Sprague-Dawley (SD) rats were randomly divided into control group，migraine model group，sodium valproatetreated group，each of the last 2 groups was divided into the attacking group and intermission group.The model of migraine was established using Cristina method，once a week for 5 weeks.After the second injection，rats in sodium valproate-treated group were given sodium valproate (0.5 g/L，10 ml/kg) everyday，and those in control group and model group were given normal saline solution (10 ml/kg).After the fifth injection，at the second hour (attacking groups) or the fourth day (intermission groups and control group)，reverse transcription-polymerase chain reaction was used to detect the expression level of GABAA receptor α1 mRNA in brainstem and trigeminal ganglion. Results The expression level of GABAA receptor α1 mRNA in modeling attacking group (1.50±0.13) was higher than any other group (control group:1.01±0.24，modeling intermission group:1.04±0.10，sodium valproate-treated attacking group:0.99±0.22，sodium valproate-treated intermission group:0.72±0.03)，and it was significantly higher than modeling intermission group (χ2=9.490，P=0.009).There was no statistical difference between modeling group and any other group，and compared with control group，there was no statistical difference in sodium valproate-treated attacking group or intermission group. Conclusion The pathogenesis of migraine may be related to the expression level of GABAA receptor α1 mRNA. Key words: Migraine disorders; Receptor，GABA-A; RNA，messenger; Brain stem; Trigeminal nerve; Valproic acid