Journal: The Journal of Physiology
Article Title: An Id-like current that is downregulated by Ca2+ modulates information coding at CA3-CA3 synapses in the rat hippocampus
Figure Lengend Snippet: An I D -like current activated from the resting membrane potential is blocked by low doses of 4-AP A , firing response upon injection of a steady inward current (0.1 nA for 800 ms) from a resting membrane potential of -61 mV. Notice the afterhyperpolarisation at the end of the pulse. B , increasing the stimulation intensity (0.2 nA) produced in the same neurone repetitive firing with strong adaptation followed by a prominent afterhyperpolarisation. C , upon membrane hyperpolarisation (-68 mV), the same neurone responded to a current step of 0.2 nA with a reduced number of spikes and with a larger delay in the appearance of the first action potential. Insets in A - C represent the same traces on an expanded time scale. D , mean delay to the appearance of the first spike from the resting membrane potential (control, ctl, -56 ± 1 mV; n = 12) and from a more hyperpolarised membrane potential (hyper, -66 ± 1 mV). E and F , voltage responses to a 0.2 nA current step in control conditions ( E ) and in the presence of 4-AP ( F ) for a different neurone. G , mean delay to the generation of the first spike in control conditions and in the presence of 4-AP ( n = 14). H and I , firing responses to a 0.2 nA current step in control conditions ( H ) and in the presence of DTX-I (DTX, I ; scale bar as in E and F ). J , mean delay to the first spike appearance in control conditions and in the presence of DTX-I ( n = 4). * P
Article Snippet: The following drugs were used: 4-AP (Sigma); DTX-I (Alomone Labs, Jerusalem, Israel); DL-2-amino-5-phosphonopentaoic acid (D-AP5), 6,7-dinitroquinoxaline-2,3-dione (DNQX), bicuculline and CGP 55845 (all purchased from Tocris Cookson, Bristol, UK).
Techniques: Injection, Mass Spectrometry, Produced, CTL Assay