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DAVID LEÓN NAVARRO Y COLS. AN. R. ACAD. NAC. FARM.

3.5. The inhibitory effect of glutamate on ATP-mediated
3.5. responses is not associated to P2 receptor
3.5. desensitization

Since different P2X and P2Y receptors can undergo a decline in
current amplitude in response to repeated applications of ATP (24,
25), we investigated if this desensitization process could be involved

Figure 4. Effects of 100 µM NMDA (A), 100 µM AMPA (B) and 100 µM DHPG
(C) on ATP-mediated responses in somas of 9 div cultured granule neurons.
ATP-induced currents were studied 30 s and 5 min after glutamate receptor agonist
application and were compared with the first ATP-response for each neuron.
Changes in [Ca2+]i in Fura-2-loaded granule neurons following repetitive stimulation
with 200 µM ATP (D). ***, p < 0.001; **, p < 0.01: *, p < 0.05 significantly different
from first ATP-mediated response.

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