We determined the effects of either topical or systemic calcium channel antagonists on rabbit intraocular pressure (IOP). Topical nifedipine, verapamil or diltiazem had no significant effect on IOP. Intravenous verapamil and nifedipine caused statistically significant reductions in IOP between 2 and 6 h after administration; the nifedipine response followed an increase in IOP at 30 min. Diltiazem, given 3 times daily for 3 days, caused no pressure change. In the rabbit, therefore, calcium channel antagonists have no effect when given topically, but do reduce IOP when given systemically.

Fasting lipid profiles were measured in 20 selected patients the day of and after cardiac catheterization in EDTA tubes. Samples were randomly labelled A or B, centrifuged, and stored at 3 degrees Centigrade. Lipid profiles were analyzed by a laboratory, which was participating in the Center for Disease Control Lipid Standardization Program, by using standard methods. The coefficients of variation for repeated measurements were: cholesterol = 1.9%, triglycerides = 3.6%, HDL cholesterol = 4.3%, and VLDL and LDL cholesterol = 2.6%. Data were evaluated by a two-tailed paired t-test and correlation coefficient. The total cholesterol was significantly lower (P less than .001) the day after cardiac catheterization as was the LDL cholesterol (P less than .002). Both VLDL and HDL cholesterol and triglycerides were lower, but these were not statistically significant. The mean dose of heparin was 3500 +/- 1469 units, and the mean dose of contrast was 181 +/- 30 cc. The total dose of heparin or contrast did not correlate with any change in lipid profiles. These results have implications on the number and timing of venous blood sampling for lipid measurements in regard to diagnosis and treatment of hyperlipidemia. Lipid profiles should not be drawn after cardiac catheterization but rather before and/or in the free-living state.