Stimulatory effect of lead on the proliferation of cultured vascular smooth-muscle cells.
The effect of lead nitrate on the DNA synthesis of cultured bovine aortic smooth-muscle cells has been studied. Lead at 0.5-10 microM stimulated the incorporation of [3H]thymidine into the acid-insoluble fraction of the cells in a dose-dependent manner. However, other heavy metals including zinc, copper, manganese and nickel did not show such a stimulatory effect. Stimulation of [3H]thymidine incorporation by basic fibroblast growth factor was additive to that by lead. However, stimulation by either platelet-derived growth factor or acidic fibroblast growth factor was reduced by the metal. The leakage of lactate dehydrogenase into the medium from smooth-muscle cells, a marker of cell death, was not changed by the metal. Calcium ionophore A23187 inhibited [3H]thymidine incorporation in vascular endothelial cells but stimulated it in vascular smooth-muscle cells. These results suggest that lead may stimulate the proliferation of cultured vascular smooth-muscle cells probably via a calcium-dependent pathway; the metal may mimic calcium within the cells.
Fujiwara
Y
Y
Department of Environmental Science, Faculty of Pharmaceutical Sciences, Hokuriku University, Kanazawa, Japan.
Kaji
T
T
Yamamoto
C
C
Sakamoto
M
M
Kozuka
H
H
D000818:Animals; D001011:Aorta / Q000166:cytology; D002417:Cattle; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004730:Endothelium, Vascular / Q000166:cytology / Q000187:drug effects; D007854:Lead / Q000494:pharmacology*; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects*
D007854:Lead