title: Improvement of postischemic, contractile function by the calcium channel blocking agent nitrendipine in conscious dogs.
abstract: The effect of the new calcium channel blocking agent, nitrendipine, on recovery of contractile function following a 10-min left anterior descending coronary artery occlusion was studied in conscious dogs instrumented with sonomicrometers in the subendocardium of ischemic and normal regions. Nitrendipine (1.0 and 2.5 micrograms/kg/min i.v.) or drug vehicle was administered 30 min prior to the onset of coronary artery occlusion and continued for 30 min following reperfusion accomplished by inflation and deflation of a vascular balloon cuff. Nitrendipine produced a dose-related reduction in arterial pressure and an increase in heart rate and left circumflex coronary blood flow velocity. At 6 h following reperfusion in control dogs (N = 8), segment shortening was significantly reduced from control levels (71 +/- 10% of control). In comparison, dogs pretreated with nitrendipine (3 micrograms/kg/min i.v.) (n = 8) had significantly greater recovery of segment shortening throughout the reperfusion period (102 +/- 10% of control at 6 h following reperfusion). The data demonstrate that pretreatment with the calcium channel blocking agent enhances the recovery of function in postischemic, reperfused, "stunned" myocardium.
authors: Department of Pharmacology, Medical College of Wisconsin, Milwaukee 53226.
authors: D C
authors: DC
authors: Warltier
authors: G J
authors: GJ
authors: Gross
authors: H L
authors: HL
authors: Brooks
authors: K C
authors: KC
authors: Preuss
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D003326:Coronary Circulation / Q000187:drug effects; D003327:Coronary Disease / Q000188:drug therapy* / Q000503:physiopathology; D004285:Dogs; D006339:Heart Rate / Q000187:drug effects; D009200:Myocardial Contraction / Q000187:drug effects*; D009568:Nitrendipine / Q000494:pharmacology*; D010477:Perfusion; D011433:Propranolol / Q000494:pharmacology; D013997:Time Factors
chemical_list: D009568:Nitrendipine; D011433:Propranolol