Fig. 1.

Photolysis of caged ATP (NPE-ATP) evokes synaptic currents in mitral cells. a Repetitive application of ATP by photolysis of NPE-ATP (100 μM) evokes inward currents with decreasing amplitudes. b Photorelease of ATP increases the frequency of postsynaptic currents. Inset: The averaged current of fast synaptic events before application of ATP (Control, thin line) is not significantly altered during application of ATP (bold line). Scale bars: 50 ms; 50 pA. c The ATP-induced inward currents, as measured as the integral of the current trace, decreased upon the second and third photolysis of caged ATP compared to the first photolysis. *, p < 0.05; ***, p < 0.005. d The ATP-elicited increase in the frequency of postsynaptic currents remained constant at all three photolysis of ATP. ns, not significant. e In current clamp mode, photolysis of caged ATP results in a membrane depolarisation