Serum from patients with restenosis after percutaneous transluminal coronary angioplasty stimulates proliferation of bovine vascular smooth muscle cells under low extracellular calcium condition.

Abstract

We compared the effects on the proliferation of bovine vascular smooth muscle cells (VSMC) of serum from 36 patients without restenosis (group A), and 21 patients with restenosis (group B) after percutaneous transluminal coronary angioplasty (PTCA). Baseline characteristics were similar in both groups, except for the greater number of patients with unstable angina at the time of PTCA (52 vs 22%, p = 0.020) and the shorter interval between PTCA and repeat angiography in group B (106 +/- 30 vs 153 +/- 112 days, p = 0.022). Cultured bovine VSMC were stimulated with patient serum (5%) obtained at repeat angiography in either Ca(2+)-containing or Ca(2+)-free culture medium. DNA synthesis was assessed by [3H]thymidine incorporation. The following indices of VSMC proliferation were used: S(+) = [3H]thymidine uptake stimulated by 5% serum in Ca(2+)-containing medium/[3H]thymidine uptake stimulated by 5% fetal calf serum (FCS) in Ca(2+)-containing medium, S(-) = [3H]thymidine uptake stimulated by 5% serum in Ca(2+)-free medium/[3H]thymidine uptake stimulated by 5% FCS in Ca(2+)-free medium, and D = S(-)-S(+). D represented the preserved DNA synthesis in Ca(2+)-deprived medium. S(-) was lower than S(+) in group A (1.35 +/- 0.56 vs 1.57 +/- 0.58, p less than 0.0001), whereas it was higher than S(+) in group B (1.64 +/- 0.66 vs 1.50 +/- 0.58, p = 0.010). D was significantly higher in group B than in group A (0.14 +/- 0.23 vs -0.22 +/- 0.28, p less than 0.0001), and was not associated with any continuous variables including serum calcium level on univariate regression analysis.(ABSTRACT TRUNCATED AT 250 WORDS)