Kinetics of low threshold calcium channels of relay cells in cat lateral geniculate nucleus

Kinetics of the low threshold T-type Ca2+ channel is studied with single electrode voltage clamp technique on brain slices of the cat lateral geniculate nucleus (LGN). Space clamp is dramatically improved by blocking various K+ and Na+ channels, decreasing Ca2+ current and selecting proper holding potentials. Results from this study are similar to those obtained from acutely dissociated LGN neurons of the rat, indicating that the kinetics of T-Ca2+ channels of the cat LGN neurons is the same as that of the rat LGN. The result reported previously on the cat LGN may result from a defect in space clamp.