Density-dependent hyperpolarization in cultured aortic smooth muscle cells.
The membrane potential (Em) of cultured aortic smooth muscle cells from Sprague-Dawley (SD), Wistar-Kyoto (WKY), and spontaneously hypertensive (SHR) rats was measured in proliferating primary cultures. Em of SD cells in high-density cultures was -51 to -58 mV, whereas that of low-density cultures (1-2 days) was -30 mV. This difference was due to a continuous process of hyperpolarization during proliferation in culture. Em of WKY and SHR hyperpolarized similarly, from -12 to -42 and -38 mV, respectively. Hyperpolarization of Em of SD, WKY, and SHR cells was related to cell density rather than time in culture. Em may be a sensitive and significant indicator of the changes in the differentiated state expressed by proliferating smooth muscle in vitro.
Blennerhassett
M G
MG
Department of Neurosciences, Faculty of Health Sciences, McMaster University, Hamilton, Ontario, Canada.
Kannan
M S
MS
Garfield
R E
RE
D000818:Animals; D001011:Aorta / Q000166:cytology / Q000502:physiology*; D002455:Cell Division; D002478:Cells, Cultured; D002999:Clone Cells; D004553:Electric Conductivity; D007700:Kinetics; D008297:Male; D008564:Membrane Potentials; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000502:physiology*; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains; D011921:Rats, Inbred WKY; D013997:Time Factors