The Role of Ca^(2+) and Cyclic AMP in the Modulation of BenzodiazepineReceptor on Aldosterone Secretion

摘要

PK11195, a ligand of peripheral-type benzodiazepine receptor can stimulate thealdosterone secretion of isolated adrenal glomerulosa cell: this effect could be abolished by nifedipinewhich mainly blocks the calcium channel in plasma membrane, but could not be abolished bydantrolene, a selective blocker of mitochondria calcium channel. Even under the condition of themaximum stimulative effects on aldosterone secretion, PK11195 could not change the cyclic AMP（cAMP） content in isolated glomerulosa cells. These results indicated that in the modulatory mecha-nism of benzodiazepine receptor on aldosterone secretion, the intracellular messenger might be theCa2+ from extracellular Ca2+ pool, but not the Ca2+ from mitochondria Ca2+ pool or cAMP.