Fig. 3.

Nitroglycerin (GTN) and sodium nitroprusside (SNP) increased the expression and phosphorylation of protein kinase C (PKC)γ and PKCε isoforms, cyclic AMP response element binding protein (CREB), and signal transducer and activator of transcription 1 (STAT1) within the dura mater. (A) Nitroglycerin (GTN) (10 mg/kg  i.p.) and SNP (1 mg/kg  i.p.) increased the expression of phosphorylated PKCγ (pPKCγ) at 1, 2, and 4 h after administration. (B) The nitric oxide (NO) donors also increased the expression of pPKCε with a peak at 1 h after administration. (C) An influence on meningeal CREB protein levels was detected as revealed by reduced contents after GTN and SNP treatment. (D) An increased expression of phosphorylated CREB (pCREB) after NO donors’ administration was observed 2 h after SNP treatment. (E) The phosphorylation of STAT1 protein (pSTAT1) was increased 1, 2, and 4 h after SNP (1 mg/kg  i.p.) treatment. The columns represent the densitometric quantitation of immunoreactive protein expressed relative to the control. Representative immunoblots are reported on each panel. *P < 0.05, **P < 0.01, and ***P < 0.001 compared with the control group