ATP stimulates calcium influx in primary astrocyte cultures
The effect of ATP and other purines on /sup 45/Ca uptake was studied in primary cultures of rat astrocytes. Treatment of the cells with ATP for 1 to 30 min brought about an increase in cellular /sup 45/Ca. Stimulation of calcium influx by ATP was investigated using a 90 sec exposure to /sup 45/Ca and over a concentration range of 0.1 nM to 3 mM; a biphasic dose-response curve was obtained with EC50 values of 0.3 nM and 9 uM, indicating the presence of low and high affinity purinergic binding sites. Similar levels of /sup 45/Ca influx at 90 sec were observed with ATP, ADP and adenosine (all at 100 uM). Prior treatment of the cultures with LaCl3 blocked the purine-induced /sup 45/Ca influx. These findings indicate that one pathway for calcium entry in astrocytes involves purinergic receptor-operated, calcium channels.
- Research Organization:
- Veterans Administration Medical Center, Miami, FL (USA)
- OSTI ID:
- 6499987
- Journal Information:
- Biochem. Biophys. Res. Commun.; (United States), Vol. 157:3
- Country of Publication:
- United States
- Language:
- English
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ADENOSINE
BIOCHEMICAL REACTION KINETICS
ADP
ATP
CALCIUM
MEMBRANE TRANSPORT
ANIMAL CELLS
BIOLOGICAL PATHWAYS
CALCIUM 45
CALMODULIN
DOSE-RESPONSE RELATIONSHIPS
NERVE CELLS
RATS
RECEPTORS
TRACER TECHNIQUES
ALKALINE EARTH ISOTOPES
ALKALINE EARTH METALS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
CALCIUM ISOTOPES
DAYS LIVING RADIOISOTOPES
ELEMENTS
EVEN-ODD NUCLEI
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
MAMMALS
MEMBRANE PROTEINS
METALS
NUCLEI
NUCLEOSIDES
NUCLEOTIDES
ORGANIC COMPOUNDS
PROTEINS
RADIOISOTOPES
REACTION KINETICS
RIBOSIDES
RODENTS
SOMATIC CELLS
VERTEBRATES
550201* - Biochemistry- Tracer Techniques