Effect of 7-nitroindazole on the expression of intracellular calcium channels in the kidney of spontaneously hypertensive rats

Abstract

The spontaneously hypertensive rats (SHR) were fed with nitric oxide synthase (NOS) blocker 7-nitroindazole (7-NI, 10 mg/kg/day) for 6 weeks and an expression of intracellular calcium channels, SERCA and proapoptotic agents was evaluated in kidney. Treatment of rats with 7-NI resulted in a significant increase in mRNA and protein levels of the IP3 receptors type 1 and type 2, while mRNA levels of the IP3 receptor type 3 remained unchanged. The mRNA of other intracellular calcium channels, ryanodine receptors type 1 and type 2 was also upregulated by 7-NI treatment. Gene expression of the SERCA2a, calcium pump responsible for loading intracellular stores with calcium, revealed increased gene expression due to 7-NI as well. Interestingly, proapoptotic agents caspase 3 and Bax were also upregulated by the 7-NI treatment. These results may indicate that nNOS blocker 7-NI modifies intracellular calcium transport system, which may have impact on altered calcium handling and regulation of various metabolic pathways.