Figure 1. Endogenous α1-ARs Localize to the Nuclei in Adult Cardiac Myocytes.
(A) Freshly isolated wild-type adult cardiac myocytes were fractionated by homogenization and sucrose density gradient ultracentrifugation. Isolated nuclei were stained with BODIPY-prazosin, counter-stained with Hoechst 33342, mounted on coverslips, and visualized by confocal microscopy. Original magnification = 1200x. (n=3 separate isolations) (B) Cultured α1ABKO adult cardiac myocytes were infected with adenovirus expressing α1B-GFP and, after 40 hrs, cardiac myocytes were fractionated as in (A). Isolated nuclei were mounted on coverslips and visualized by confocal microscopy. Original magnification = 1200x. (C) Membrane, cytosol, and nuclear fractions (30 µg) from freshly isolated adult cardiac myocytes were validated by Western blots for Na+/Ca2+ exchanger, GAPDH, or LAP2 respectively. Representative Western blots are shown. Similar results were obtained from cultured cardiac myocytes as we previously described [27].