Fig. 7

NEDD (neural precursor cell expressed developmentally downregulated protein) 4-1-dependent downregulation of L-type calcium channel (LTCC) by LITAF (lipopolysaccharide-induced tumor necrosis factor) in 3-wk-old rabbit cardiomyocytes. A, Protein levels of total Cavα1c (L-type calcium channel alpha-1C subunit), NEDD4-1, and tubulin in cells expressing scrambled control RNA or shRNA against endogenous NEDD4-1 ( left; the asterisk indicates an unspecific band). Respective changes in NEDD4-1 and Cavα1c abundance, normalized to tubulin (n=5 animals, performed in triplicate; mean±SEM). Student t test, P<0.05 ( right). B, Current-voltage relationships of LTCC current (ICa,L) peak currents for baseline conditions from cells expressing GFP (green fluorescence protein) and short hairpin RNA (shRNA) against endogenous NEDD4-1 (control) or LITAF and NEDD4-1 shRNA. C, Three-week-old rabbit cardiomyocytes were transduced with adenovirus expressing scrambled RNA and LITAF (control) or LITAF and shRNA against endogenous NEDD4-1. Current-voltage relationships of ICa,L peak currents for baseline conditions from respective cells are depicted (cells from 5 animals; mean±SEM; Student t test, P<0.05).