Figure 4. CRF Interacts with Phenylephrine to Drive LTP without IP3-Induced Ca2+ Signal Facilitation.
(A) Summary time graph (left) and example traces (right) showing that CRF augments facilitation of AP-evoked IK(Ca) produced by a low concentration (0.5 μM) of phenylephrine (7 cells from 5 rats).
(B) Graph plotting the magnitude of IK(Ca) facilitation caused by phenylephrine (0.5 μM) alone and by phenylephrine and CRF in individual cells; t(6) = 2.22, *p < 0.05, two-tailed paired t test.
(C) Representative experiment to induce LTP in the presence of both CRF and phenylephrine (0.5 μM) using an induction protocol consisting of synaptic stimulation-burst pairing with no preceding IP3 application. Example EPSC traces at the times indicated are shown in inset (scale bars: 50 ms/50 pA).
(D) Summary time graph of LTP experiments in which LTP was induced using a synaptic stimulation-burst pairing protocol in the presence of both CRF and phenylephrine (0.5 μM) (7 cells from 4 rats).
Data are presented as mean ± SEM.