Figure 5

BK channel current densities in adrenal gland chromaffin cells from WT and KO mice, with or without castration. Outward potassium current densities were recorded with the perforated patch clamp technique in the absence or presence of paxilline (Pax; 10 μM), a BK channel blocker. Current-voltage curves are presented as means ± S.E. of I(pA/pF). Curves are generated from pooled data from 4–12 cells from 2–5 different mice: WT (n = 7 cells from 4 mice), KO (n = 12 cells from 3 mice), castrated WT (n = 8 cells from 5 mice), castrated KO (n = 4 cells from 2 mice). *p < 0.05 (2-tailed Student’s t test). (A) KO adrenal gland chromaffin cells showed higher voltage-gated K⁺ current densities. (B) Voltage-gated K⁺ current densities were almost abolished by the BK channel blocker paxilline. (C) KO adrenal gland chromaffin cells showed higher voltage-gated, paxilline-sensitive K⁺ current densities. (D) Castration significantly decrease voltage-gated paxilline-sensitive K⁺ current densities in KO adrenal gland chromaffin cells. (E) Castration did not significantly change voltage-gated, paxilline-sensitive K⁺ current densities in WT adrenal gland chromaffin cells. (F) Paxilline-sensitive BK current densities from WT and KO adrenal gland chromaffin cells become similar after castration.