Synchronous calcium oscillations in cerebellar granule cells in culture mediated by NMDA receptors.
The concentration of cytosolic Ca2+ ([Ca2+]i) was monitored in cerebellar granule cell cultures by digital imaging of fura-2 loaded cells. In the presence of Mg2+, cells grown in low K+ cultures responded to N-methyl-D-aspartate (NMDA) with uniform increases in [Ca2+]i from a stable basal [Ca2+]i. In contrast, in Mg(2+)-free medium, low K+ cultures showed spontaneous, synchronized [Ca2+]i oscillations from 4 days in culture. The oscillations were rapidly blocked by Mg2+, D,L-2-amino-5-phosphonovalerate, or tetrodotoxin. The development of oscillatory behaviour depended on the culture conditions and was not observed in cultures grown in high K+. These data show a high degree of connectivity established within 4 days in culture by dissociated granule cells allowing synchronized activity mediated through synaptic mechanisms.
Lawrie
A M
AM
Physiological Laboratory, University of Liverpool, UK.
Graham
M E
ME
Thorn
P
P
Gallacher
D V
DV
Burgoyne
R D
RD
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002478:Cells, Cultured; D002531:Cerebellum / Q000166:cytology / Q000378:metabolism*; D003594:Cytoplasmic Granules / Q000378:metabolism*; D007091:Image Processing, Computer-Assisted; D008274:Magnesium / Q000494:pharmacology; D016202:N-Methylaspartate / Q000494:pharmacology; D011188:Potassium / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*
D016194:Receptors, N-Methyl-D-Aspartate; D016202:N-Methylaspartate; D015763:2-Amino-5-phosphonovalerate; D008274:Magnesium; D011188:Potassium; D002118:Calcium