Angiotensin II increases c-Fos and c-Jun mRNA Expression in Cultured Rat Astrocytes.

Signature Grand, Davie, Florida, USA

Background. Previous studies, in vascular smooth muscle and other peripheral cells, have shown that angiotensin II (Ang II) induces the expression of several early response genes in human and rats including c-fos, c-jun, c-myc and NF-kappa B. Stimulation of early response genes by Ang II is associated with increased gene expression and production of growth factors, vasoconstrictor agents, adhesion molecules, and chemotactic factors. Objective. To determine the effects of Ang II on the expression of c-fos and c-jun in medullary and cerebral rat astrocytes. Methods. Brainstem and cerebellum astrocytes were treated with 100 nM Ang II for 15 to 90 minutes and mRNA was extracted. Using specific primers for c-fos and c-jun, rt-PCRs were performed and amplicons were separated by gel electrophoresis. Results. Ang II stimulated the mRNA expression of c-fos and c-jun in a time-dependent manner. This effect was observed as early as 15 minutes and was still apparent even 90 minutes after Ang II stimulation. Conclusions. The findings of this study show for the first time that Ang II stimulates the mRNA expression of c-fos and c-jun in astrocytes and suggest a role for Ang II in the regulation of early response genes in the CNS. Further studies are underway to determine the relevance of this finding in the central regulation of blood pressure. Grants. Supported by a NSU President's Faculty Research & Development Grant and a NHLBL R15 HL077199-01.