Therefore, transretinal ERG is expected to give the same τD values as the suction pipette method (or membrane potential recording) taken that components other than those of photoreceptor origin are carefully abolished.
After 20 to 30 minutes whole-cell membrane potential recording, small dendrites and spines were sufficiently labeled and a spine and neighboring dendrite were selected for point imaging (Fig. 1A).
For example, if the membrane potential recorded at time t is –70 mV, and the value that was sampled 125,000 steps before was –60 mV, a frequency of 25 kHz would give a momentum of –20 mV/s, which means that around time t the membrane tends to hyperpolarize at a rate of some –20 mV every second.
(H ) A trace of membrane potential recorded from the cell in response to cosine current injections of varying frequency.
Addition of 100 μM KCN caused a sustained depolarization of the mean membrane potential recorded during gamma oscillations (−50.4 ± 5.37 mV control versus −37.2 ± 2.98 mV KCN, P < 0.05) and produced an almost complete abolition of firing (9.92 ± 1.75 Hz control versus 0.11 ± 0.07 Hz KCN, P < 0.05).
The high degree of correlation of membrane potentials recorded from close-by neurons (Lampl et al. 1999) and the similarity of LFPs taken at distant recording sites (Destexhe et al. 1999) suggests that these oscillatory network fluctuations revealed in the LFP act as average input in a neuron-unspecific manner.
Immediately after attaining a stable whole-cell recording, the resting membrane potential was recorded in current-clamp mode.
For voltage-clamp recordings in the presence of cesium, no resting membrane potential was recorded.
Data was collected using a DI-720 Series #3 Data Acquisition System Dataq Instrumentss, Inc., Akron, OH) controlled by WinDaq Waveform Recording Software, and was analyzed using WinDaq Waveform Browser (Dataq Instruments, Inc .. Individual cells were impaled, and membrane potential was recorded relative to the bath solution (HBSS, Invitrogen).
