ABSTRACT
Sophora flavescens Ait. (Fabaceae) is a medicinal plant widely founded in Northeast Asia, and its dried root (Kushen) has been used as a traditional Chinese herbal medicine. The therapeutic effects of Kushen in micturition disorder was not investigated comprehensively yet. In the present study, we examined and compared the efficacy of three batches of Kushen extract using different ethanol content through an in vitro cell-based assay. Among them, we chose the batch with the highest efficacy and augmented the volume of extract for industrial purpose. The bulk extract was examined in its efficacy in the in vitro cell-based assay, and the therapeutic effects through an in vivo behavioral assay of OAB rats. The main components of the extracts were analyzed by liquid chromatography. Cytotoxicity of the extracts was investigated by MTT assay. The overall efficacy of the extract was as much as, or more than, kurarinone, a potent BKCa channel activator. Thus, the extract was a potent relaxant of urinary smooth muscle by upregulating the activity of BKCa channel. The Kushen extract could be explored as an alternative medicine against overactive bladder patients indicating severe dysfunction of BKCa channel
ABSTRACT
Sophora flavescens Ait. (Fabaceae) is a medicinal plant widely founded in Northeast Asia, and its dried root (Kushen) has been used as a traditional Chinese herbal medicine. The therapeutic effects of Kushen in micturition disorder was not investigated comprehensively yet. In the present study, we examined and compared the efficacy of three batches of Kushen extract using different ethanol content through an in vitro cell-based assay. Among them, we chose the batch with the highest efficacy and augmented the volume of extract for industrial purpose. The bulk extract was examined in its efficacy in the in vitro cell-based assay, and the therapeutic effects through an in vivo behavioral assay of OAB rats. The main components of the extracts were analyzed by liquid chromatography. Cytotoxicity of the extracts was investigated by MTT assay. The overall efficacy of the extract was as much as, or more than, kurarinone, a potent BKCa channel activator. Thus, the extract was a potent relaxant of urinary smooth muscle by upregulating the activity of BKCa channel. The Kushen extract could be explored as an alternative medicine against overactive bladder patients indicating severe dysfunction of BKCa channel
ABSTRACT
PURPOSE: Calcium-activated potassium channels(KCa) may be involved in the transient outward current of the first phase of cardiac action potential. But it is still not clear whether cardiac myocytes express any Kca. We try to identify here the types of Kc, expressed in rat caridac myocytes. METHODS: We isolated total heart RNA from 50 rats(Spague-Dawley) and performed reverse transcription-polymerase chain reaction(RT-PCR) using specifically designed synthetic oligonucleotide primer sets. From the pure culture of cardiac myocyte, Kc, gene expression was detected by Southern blot analysis. RESULTS: RT-PCR revealed expressions of BKca(large-conductance Kca, rSlo) and S&,(small-conductance Kca, rSK1). We prepared cardiac myocytes pure culture(>9596 pure myocyte) using pure culture technique. RT-PCR and Southern blot analysis of rat cardiac myocyte showed only rSK1-specific band, but no rSlo-specific was detected. CONCLUSION: The expressions of more than one type of Kca are detected from rat heart. A sub-type of SKcrSK1, was expressed in cardiac myocyte, while the main subunit of BKca(rSlo) was found in cells other than myocytes, most likely in the smooth muscle of cardiac blood vessels.