L-Type Calcium Channel Antagonists and Suppression of Expression of Plasminogen Receptors

See related article, pages 167–175 Several types of voltage-dependent Ca2+ channels were reported in many excitable and nonexcitable cell types, including the L-, T-, P-, N-, and Q-types; the isradipine sensitive steady-state resting R-type1,2; and the nifedipine resistant R-type channels.3 The presence of some of these voltage-dependent Ca2+ channel types depends on cell origin. Among these channels, the L-type is the most studied channel because of the large number of Ca2+ blockers that affect its function. Historically, calcium channel antagonists were developed before the discovery of the L-type Ca2+ channel. These Ca2+ channel antagonists are divided into 3 classes of drugs: benzothiazepines (such as verapamil), dihydropyridines (such as amlodipine), and phenylalkylamines (such as diltiazem). The 3 classes of L-type Ca2+ channel antagonists have different relative selectivity for cardiac and vascular tissues. Their effects depend on the frequency of channel opening and where they physically bind on the channel.L-type Ca2+ channel antagonists have been studied for many years in other fields of application other than blockade of calcium entry through the L-type voltage-dependent Ca2+ channel. Historically, the literature in the field of L-type Ca2+ channel blockers is full of information concerning their effects on other sites that regulate Ca2+ movements into and within cells. Among these effects are …