The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)
 
 
 
 
 

Effects of C-type natriuretic peptide on ionic currents in mouse sinoatrial node: a role for the NPR-C receptor.

The effects of C-type natriuretic peptide (CNP) on heart rate and ionic currents were demonstrated by recording the ECG from adult mice and performing voltage-clamp experiments on single sinoatrial (SA) node cells isolated from mouse heart. The selective natriuretic peptide type C receptor (NPR-C) agonist cANF (10(-7) M) significantly decreased heart rate in the presence of isoproterenol (5 x 10(-9) M), as indicated by an increase in the R-R interval of ECGs obtained from Langendorff-perfused hearts. Voltage-clamp measurements in enzymatically isolated single pacemaker myocytes revealed that CNP (10(-8) M) and cANF (10(-8) M) significantly inhibited L-type Ca2+ current [ICa(L)]. These findings suggest that the CNP effect on this current is mediated by NPR-C. Further support for an NPR-C- mediated inhibition of ICa(L) in SA node myocytes was obtained by altering the functional coupling between the G protein Gi and NPR-C. In these experiments, a "Gi-activator peptide," which consists of a 17-amino acid segment of NPR-C containing a specific Gi protein-activator sequence, was dialyzed into SA node myocytes. This peptide decreased ICa(L) significantly, suggesting that NPR-C activation can result in a reduction in ICa(L) when CNP is bound and the Gi protein pathway is activated. This effect of CNP appears to be selective for ICa(L), because the hyperpolarization-activated current was unaffected by CNP or cANF. These results provide the first demonstration that CNP has a negative chronotropic effect on heart rate and suggest that this effect is mediated by selectively activating NPR-C and reducing ICa(L) through coupling to Gi protein.[1]

References

  1. Effects of C-type natriuretic peptide on ionic currents in mouse sinoatrial node: a role for the NPR-C receptor. Rose, R.A., Lomax, A.E., Kondo, C.S., Anand-Srivastava, M.B., Giles, W.R. Am. J. Physiol. Heart Circ. Physiol. (2004) [Pubmed]
 
WikiGenes - Universities