Stimulation of α_1L-adrenoceptor, atypical α₁-adrenoceptor, activates store-operated Ca²⁺ channels and voltage-dependent Ca²⁺ channels

Dr. Keisuke Obara(left), Prof. Yoshio Tanaka(center), Dr. Kento Yoshioka(right)

A research group led by Dr. Keisuke Obara, Dr. Kento Yoshioka, and Professor Yoshio Tanaka of the Department of Chemical Pharmacology, Faculty of Pharmaceutical Sciences, Toho University, found that contractions induced by phenylephrine (a nonselective α₁-adrenoceptor agonist) in the guinea pig thoracic aorta could be triggered by stimulation of Gq protein-coupled α_1L-adrenoceptor (atypical α₁-adrenoceptor), followed by activation of store-operated Ca²⁺ channels (SOCCs) and voltage-dependent Ca²⁺ channels (VDCCs). These results suggest that 1) SOCC and/or VDCC inhibitors could suppress abnormal contractions in lower urinary and genital tissues such as prostate where α_1L-adrenoceptors are abundantly expressed, and 2) these inhibitors could be the new therapeutic agents for lower urinary and genital diseases such as benign prostatic hyperplasia, in addition to α₁-adrenoceptor antagonists. The results of this research were published in the journal “Biological and Pharmaceutical Bulletin” in February 2023.