Rhythmic oscillations of cytosolic free calcium in rat C-cells.
The relationship between stimulation of single C-cells (rMTC-6-23 cell line) with extracellular calcium, glucagon or 8-bromo-cAMP and fluctuations of intracellular free calcium concentration was studied. After pretreatment of rMTC cells with either 1 microM glucagon (30-60 min) or 1 mM 8-bromo-cAMP (5 min) [Ca2+]i started to oscillate when extracellular calcium was raised to 3 mM. These fluctuations in [Ca2+]i could be stopped by chelating the external calcium with EGTA or by adding calcium channel blockers. The voltage-dependent calcium channels in the plasma membrane seem to play a major role in maintaining the oscillations of [Ca2+]i.
Eckert
R W
RW
Institute of Cell and Tumor Biology, German Cancer Research Center, Heidelberg.
Scherübl
H
H
Petzelt
C
C
Raue
F
F
Ziegler
R
R
D015124:8-Bromo Cyclic Adenosine Monophosphate / Q000494:pharmacology; D000818:Animals; D001572:Benzofurans; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology / Q000502:physiology; D002277:Carcinoma; D000242:Cyclic AMP / Q000032:analysis; D003600:Cytosol / Q000378:metabolism; D005456:Fluorescent Dyes; D016257:Fura-2 / Q000031:analogs & derivatives*; D005934:Glucagon / Q000494:pharmacology; D051381:Rats; D013964:Thyroid Neoplasms / Q000378:metabolism*; D014407:Tumor Cells, Cultured
D001572:Benzofurans; D005456:Fluorescent Dyes; C049925:fura-2-am; D015124:8-Bromo Cyclic Adenosine Monophosphate; D005934:Glucagon; D000242:Cyclic AMP; D002118:Calcium; D016257:Fura-2