Effects of nifedipine, verapamil and diltiazem on serum biochemical parameters and aortic composition of atherosclerotic chickens.

Calcium appears to be involved in many of the cellular events, which are thought to be important in atherogenesis. In this study, we examine the effects of three calcium entry blockers (nifedipine, verapamil, and diltiazem at clinical and higher doses) on serum biochemical parameters and aortic calcium, cholesterol and triglyceride concentrations of atherosclerotic egg-fed chickens. All egg-fed chickens (treated and non-treated) showed an increase in serum total cholesterol, LDL-cholesterol and triglycerides without significant effect when calcium entry blockers were used. Increased HDL values were observed in clinical and high-dose nifedipine and clinical dose verapamil groups. The high-dose diltiazem group presented increased zinc values with respect to the clinical dose diltiazem and control groups. The sodium concentrations were significantly decreased in all the groups of animals treated with calcium entry blockers at high-doses and nifedipine at clinical doses. Measurements of aortic calcium concentration showed a significant decrease in the high-dose nifedipine and verapamil groups. Calcium channel blockers had a tendency to decrease total cholesterol in aortas. The values were statistically significant for the high-dose verapamil, and nifedipine groups. Only nifedipine showed a significant decrease for this parameter at clinical dosages. Triglyceride concentrations in aortas were significantly low in animals fed an atherogenic diet and treated with calcium channel blockers, without differences between drugs or dosages used in the experiment. In addition, the chicken atherosclerosis model has proved itself useful and very suitable for in vivo drug intervention studies.