1、Hypertensione.g. 50 millions Americans have hypertension. Incidence: 10-20% in adults第1頁/共13頁第2頁/共13頁* Effects of all types of calcium blockers is the inhibition of the L-calcium current in arterial smooth muscleCCBs* Verapamil, the first clinical useful drug of calcium channel blockers* Nifidipine,

2、 the most extensively studied of this group* Diltiazem, very popular and available worldwide第3頁/共13頁HypertensionMechanism of action: blocking L-type calcium channelOrgan system effect: relaxing smooth muscle (VSM most sensitive); reducing cardiac contractility or decreasing cardiac output; BP= CO x

3、PVR第4頁/共13頁Angia The mechanism of action is not understood Relaxation and prevention of coronary artery spasm (放松和預(yù)防冠狀動脈痙攣) Ruduction of Oxygen Utilization第5頁/共13頁第6頁/共13頁第7頁/共13頁硝苯地平硝苯地平 第8頁/共13頁Pharmacokinetics: half-life 2h ER 7h orally active agents, high first-pass effect, high plasma protein b

4、inding, and extensive metabolism第9頁/共13頁Metabolism Nifedipine is extensively metabolized to highly water-soluble, inactive metabolites accounting for 60 to 80% of the dose excreted in the urine. The elimination half-life of nifedipine is approximately two hours. Only traces (less than 0.1% of the dose) of unchanged form can be detected in the urine. The remainder is excreted in the feces in metabolized form, most likely as a result of biliary excretion. 第10頁/共13頁Reference1The Art Of Drug Synthesis Author:Douglas S.Johnson Jie Jack LI 2007 2Nife