Suspension of smooth muscle cells treated with digitonin as a model for studying the myometrial endoplasmic reticulum calcium pump.
The effect of the nonionic detergent digitonin on ruthenium red-insensitive, oxalate-stimulated, and thapsigargin-suppressed accumulation of Ca2+ by suspension of myometrial cells from ATP- and Mg(2+)-containing incubation medium was studied using passive loading with 45Ca2+. The dependence of Ca2+ accumulation by the cells on the concentration of digitonin is bell-shaped, the maximal Ca2+ uptake being observed at 0.05-0.1 mg/ml digitonin. Myocytes chemically skinned with digitonin represent a suitable experimental model for studying kinetic properties of the uterine myocyte endoplasmic reticulum Mg2+, ATP-dependent Ca2+ pump and assessing sensitivity of this Ca(2+)-transporting system to various effectors including the uterotonic octapeptide oxytocin.
Shlykov
S G
SG
Department of Muscle Biochemistry, Palladin Institute of Biochemistry, National Academy of Sciences of Ukraine, Kiev, Ukraine.
Babich
L G
LG
Kosterin
S A
SA
D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D002478:Cells, Cultured; D004072:Digitonin / Q000494:pharmacology*; D004721:Endoplasmic Reticulum / Q000187:drug effects* / Q000201:enzymology; D005260:Female; D007700:Kinetics; D008954:Models, Biological; D009215:Myometrium / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D051381:Rats
D000255:Adenosine Triphosphate; D000252:Calcium-Transporting ATPases; D004072:Digitonin