Increase in intracellular calcium ion in smooth muscle cells induced by low-density lipoprotein.
It was investigated whether low-density lipoprotein (LDL) had effects on intracellular Ca2+ concentration in the smooth muscle cell (SMC). LDL promoted SMC proliferation and increased intracellular Ca2+ by a two-phase pattern, an initial peak and a following plateau. Each phase was suppressed by treatment with ryanodine or extracellular Ca(2+)-free buffer. This increase in intracellular Ca2+ was also suppressed by anti-LDL receptor antibody. Moreover, inositol triphosphate (IP3) was elevated with short-term LDL treatment. Since SMC proliferation is the most important event in atherosclerosis and LDL is one of the main risk factors, it was concluded that LDL might trigger SMC proliferation by increasing IP3 and intracellular Ca2+ through LDL receptor.
Tasaki
H
H
Second Department of Internal Medicine, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
Yamashita
K
K
Nakashima
Y
Y
Kuroiwa
A
A
Tulenko
T N
TN
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D015544:Inositol 1,4,5-Trisphosphate / Q000096:biosynthesis; D017136:Ion Transport; D008077:Lipoproteins, LDL / Q000494:pharmacology*; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D011817:Rabbits; D011973:Receptors, LDL; D012433:Ryanodine / Q000494:pharmacology
D008077:Lipoproteins, LDL; D011973:Receptors, LDL; D012433:Ryanodine; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium