Abstract
Questions exist regarding tissue distribution of the β1 adrenergic receptor (β1-AR). The aim of this study was to investigate relative distribution patterns of the β1-AR at the protein level in a variety of human tissues by Western blot analysis. The specificity of anti-peptide antibodies was confirmed both by Western blot with recombinant β1-AR expressed as a membrane protein in E. coli and by immunoprecipitation of membranes from Sf9 cells infected with baculovirus to express the human recombinant β1-AR. β1-AR was found in all tissues examined. The relative amount of protein varied significantly between the tissues, from highest in lung and testis to very low in liver. β1-ARs were rather abundant in heart, kidney, placenta, spleen and thyroid. These results reveal unique distribution of β1-AR protein that suggests its tissue specific role. Moreover, our data demonstrate a high sensitivity of immunological detection that allows direct comparison of β1-AR subtype expression and could be used for receptor study in biopsies available in limited amounts, such as human heart biopsy.
