TRPC1 gene mRNA expression in kidney tissues of db/db mice. TRPC1 gene mRNA expression was examined using real-time RT-PCR in kidney tissue from db/db mice at 12 and 26 weeks of age, respectively. TRPC1 mRNA expression levels between db/db and db/m (control) mice at the age of 12 weeks were not significantly different (mean values 0.874 ± 0.117 SE vs. 0.697 ± 0.061, p = 0.295, a). The expression levels of TRPC1 in kidney tissue from 26-week-old db/db mice, however, were significantly decreased compared with the db/m controls (0.836 ± 0.062 vs. 0.601 ± 0.047, p = 0.013, b).