The name is absent

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3.2 Molecular and Biophysical Properties

3.2.1 Whole-cell currents

Recordings of whole cell currents were made from rods and cones in the whole mount retina.
We chose the whole mount retinal preparation over the dissociated rod and cone prepara-
tions in order to avoid adverse effects associated with enzymatic or mechanical dissociation
such as changes in channel kinetics∕gating or loss of axon terminals. We found that con-
tributions from adjacent rods to recorded currents via coupling were minimal, and did not
affect our results (see Recordings in Methods for explanation), as our data recorded from
the intact retina also agrees with experiments on dissociated salamander rods performed
by us (figure 3.1 Al) and other researchers [54]. For whole cell recordings, an extracellu-
lar solution containing TEA, cobalt and barium was used to block all other ionic currents
other than I_h (see Solutions in Methods). Although the whole cell properties of the I_h cur-
rent have been examined before in dissociated salamander photoreceptors or by using sharp
electrodes [1, 75, 78, 54], we felt the need to characterize them in our experiments using
whole cell voltage clamp in the intact retina, and standardize the recording conditions be-
tween rods and cones. This standardization allows us to directly compare our rod and cone
data, compare results obtained from dark- and light-adapted conditions, and use our single
channel current data to estimate the number of channels present in each cell.

Our results show that the kinetic properties of I_h in whole-cell recordings of rods and
cones are very similar, which suggests that the same channels carry I_h in both cell types. We
also found that physiological properties of I_h in rods and cones in dark-adapted conditions

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