The regulation and its mechanism of Polydatin on the ?-adrenoreceptor in cardiac myocytes stimulated by lipopolysaccharide / 中国药理学通报

ABSTRACT

Aim To observe the effect of polydatin(PD) on the activities of ?-AR in cardiomyocytes under the stimulation of LPS. Methods Cardiac myocytes were isolated and cultured from neonatal rats. Radioligand binding assay and flow cytometry were used to detect the function of ?-AR. Results In control group, the density of ?-AR (B max) was 4.14?1.41 fmol?(1?105 cells) -1 and ?-AR affinity (K d) was (4.02?0.59) nmol?L -1. In LPS group, ?-AR density was down-regulated 〔B max=1.78?0.12 fmol?(1?105 cells) -1〕 and the affinity decreased (K d=23.88?2.34 nmol?L -1). In LPS+PD group, ?-AR B max was recovered to 3.37?0.36 fmol?(1?105 cells) -1 and the affinity increased (K d=3.44?0.44 nmol?L -1). In PD group, ?-AR functions had no significant difference with normal group 〔B max=2.76?0.32 fmol?(1?105 cells) -1 and K d=4.63?1.54 nmol?L -1〕. The ?-AR amount measured by flow cytometry showed the same change tendency as the radioligand binding assay. Conclusion ?-AR activities may be down-regulated during the pathological process of LPS treatment. PD could reverse the effects of LPS by up-regulating ?-adrenoreceptors.