奎尼丁鹽酸鹽抑制劑Quinidine is an optical isomer of quinine, extracted from the bark of the Cinchona tree and similar plant species. It prolongs cellular action potential and decreases automaticity. This alkaloid dampens the excitability of cardiac and skeletal muscles by blocking sodium and potassium currents across cellular membranes. Quinidine also blocks muscarinic and alpha-adrenergic neurotransmission.
