Identification of types of GABAA receptors in neurons in brain tissues at target of anesthetic action of isoflurane in mice / 中华麻醉学杂志

ABSTRACT

Objective To identify the types of γ?aminobutyric acid type A ( GABAA ) receptors in neurons in brain tissues at the target of anesthetic action of isoflurane in mice. Methods Two mouse strains were developed that were either sensitive or resistant to isoflurane. One hundred isoflurane?sensitive ICR∕CD?1 mice ( 50 males, 50 females) and 100 isoflurane?resistant ICR∕CD?1 mice ( 50 males, 50 fe?males) , aged 65-70 days, were used in this study. Brain tissues were obtained, and total RNA was ex?tracted and then reverse transcribed to cDNA using AMV reverse transcriptase. Polymerase chain reaction was used to detect the cDNA sequences. Chi?square analysis was used to compare the cDNA sequence of each GABAA receptor subunit between two strains. Results The cDNA sequence of GABAA receptor sub?units α1?6 , β2,3 andγ1?3 in isoflurane?sensitive strain was completely consistent with that in isoflurane?resist?ant strain. A single nucleotide polymorphism at the nucleotide position 462 ( C∕G) in the β1 sequence was found. The allele C frequencies were 11.0% and 87.0% in isoflurane?sensitive strain and isoflurane?resistant strain, respectively. Compared with isoflurane?sensitive strain, the allele C frequency in cDNA sequences of β1 subunit was significantly increased in isoflurane?resistant strain ( P<0.01) . Conclusion β1 subunit?containing GABAA receptor in neurons in brain tissues is the target of anesthetic action of isoflurane in mice.