Figure 3.
![SPD3+ and SPD4+ blockade described withScheme 1.(A) Mean fractional MthK current over a range of [SPD3+], with Scheme 1 predictions superimposed (solid red curves). This model predicts that MthK currents approach 100% blockade with very strong depolarization, and thus provides a poor description of the data over the observed range of voltage and [SPD3+]. (B) Mean fractional MthK current over a range of [SPM4+], with Scheme 1 predictions superimposed. As with SPD3+, Scheme 1 predicts that MthK currents approach 100% blockade with very strong depolarization and is thus inconsistent with the data over the observed range of voltage and [SPM4+].](https://cdn.rupress.org/rup/content_public/journal/jgp/152/7/10.1085_jgp.201912527/3/jgp_201912527_fig3.png?Expires=1767736008&Signature=KIleB4Qkuf1aBOV-8j584~e5u7mDUTKoRkQp3vKXaFaIHYtxccj5IYJP6qHYBvy~4cfWOLAF2lDt4l3mEhTEUgl4gIGmbts0Q8XWIG46KMFfU5dRgsoV0nqJ1w5Z3QDtO-~IHWZKbSvaqXW0G3cnIylSFGONQrTPdhL7IG-BwwRiX3drY0pL8qiqCXhCMoFhmQXUELzFZNVqAEJ5hw2P2~qyZXxCnHqp11ByPAMmAjNMwvgtv8tuG2MD~fRmyEeB-wv1wRbOi5jSlouApKGoAiaK08~FRRQWYiCAW1gP9e1DXpQh7F4slVT7NMiVZo2dRLn7cSYq4RCJ377~5-RO4w__&Key-Pair-Id=APKAIE5G5CRDK6RD3PGA)
SPD3+ and SPD4+ blockade described with Scheme 1 . (A) Mean fractional MthK current over a range of [SPD3+], with Scheme 1 predictions superimposed (solid red curves). This model predicts that MthK currents approach 100% blockade with very strong depolarization, and thus provides a poor description of the data over the observed range of voltage and [SPD3+]. (B) Mean fractional MthK current over a range of [SPM4+], with Scheme 1 predictions superimposed. As with SPD3+, Scheme 1 predicts that MthK currents approach 100% blockade with very strong depolarization and is thus inconsistent with the data over the observed range of voltage and [SPM4+].