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Few data are available concerning single Ca channel properties in inner ear hair cells, and particularly none in vestibular type I hair cells. By using the cell-attached configuration of the patch-clamp technique in combination with the semicircular canal crista slice preparation, we determined the elementary properties of voltage-dependent Ca channels in chicken embryo type I and type II hair cells. The pipette solutions included Bay K 8644. With 70 mM Ba in the patch pipette, Ca channel activity appeared as very brief openings at –60 mV. Ca channel properties were found to be similar in type I and type II hair cells; therefore, data were pooled. The mean inward current amplitude was -1.3 pA at – 30 mV (± 0.1 SD; n = 16). The average slope conductance was 21 pS (n = 20). With 5 mM Ba in the patch pipette, very brief openings were already detectable at –80 mV. The mean inward current amplitude was -0.7 pA at –40 mV (± 0.2 SD; n = 9). The average slope conductance was 11 pS (n = 9). The mean open time and the open probability increased significantly with depolarisation. Ca channel activity was still present and unaffected when ωagatoxin IVA (2 μM) and ω-conotoxin GVIA (3.2 μM) were added to the pipette solution. Our results show that type I and type II hair cells express L-type Ca channels with similar properties. Moreover, they suggest that in vivo Ca influx might occur at membrane voltages more negative than –60 mV. Page 2 of 48