Posttranscriptional activation of BNP gene expression in response to increased left ventricular wall stress: role of calcineurin and PKC.
To study the molecular mechanisms for load-induced activation of BNP gene expression, increased wall stress was imposed on isolated isovolumetrically beating adult rat hearts by distension of a fluid filled balloon within the left ventricle. The wall stress for 2 h resulted in a 1.6-fold increase in the expression of BNP gene and a 2.0-fold increase of the c-fos gene. The inhibition of transcription by actinomycin D significantly decreased the baseline BNP mRNA levels but the wall stretch-induced increase of the gene expression remained unaffected. In contrast, the protein synthesis inhibitor cycloheximide increased baseline BNP mRNA levels and abolished the load-induced activation of gene expression. Furthermore, we studied the effects of protein kinase C ( PKC), calcineurin and protein phosphatase 2A (PP2A) inhibition to characterize the role of intracellular pathways in the stretch-induced gene expression in the left ventricle. The expression of BNP and c-fos genes were not influenced by calcineurin, PP2A and PKC inhibition. In conclusion, we showed that the stretch-induced activation of BNP gene expression by increased left ventricular wall stress is independent of transcriptional mechanisms and dependent on protein synthesis. Moreover, our results suggest that the load-induced activation of BNP gene expression is independent of calcineurin, PKC and PP2A.[1]References
- Posttranscriptional activation of BNP gene expression in response to increased left ventricular wall stress: role of calcineurin and PKC. Tenhunen, O., Szokodi, I., Ruskoaho, H. Regul. Pept. (2005) [Pubmed]
Annotations and hyperlinks in this abstract are from individual authors of WikiGenes or automatically generated by the WikiGenes Data Mining Engine. The abstract is from MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.About WikiGenesOpen Access LicencePrivacy PolicyTerms of Useapsburg