Influence of smoking on the gene expression of insulin receptor substrate 2 in rat muscle tissue

RT-PCR and immunohistochemistry were used to measure the mRNA and protein expression of insulin receptor substrate 2 (IRS-2) in the muscle of smoking rats. The mRNA and protein expressions of IRS-2 in the smoking subgroups fed with normal diet or high-fat diet were significantly lower than those in corrsponding control groups (0.27±0.02 vs 0.41±0.25, 0.40±0.04 vs 0.51±0.02 for mRNA; 2.91±0.42 vs 4.90±0.29, 2.43±0.36 vs 3.80±0.30 for protein, all P 0.05). The variation of gene expression of IRS-2 may be involved in the mechanism of insulin resistance caused by smoking. Key words: Insulin resistance;  Insulin receptor substrate 2;  Muscle, skeletal;  Smoking