In the mammalian myocardium, potassium (K ) channels control resting potentials, action potential waveforms, automaticity, and refractory periods and, in most cardiac cells, multiple types of K channels that subserve these functions are expressed. Molecular cloning has revealed the presence of a large number of K channel pore forming ( ) and accessory ( ) subunits in the heart, and considerable...

does not allow the transmission of an arbitrary channel. In most situations a receiving process k?(k′′).Q can be alpha-converted ahead of communication so that the bound channel k′′ syntactically matches the free channel k′ in the object of the sending process [11]. The exception happens exactly when k′ is free in Q: alpha-conversion becomes impossible (for it would capture the free variable k′...

The Kv2.1 voltage-activated K+ channel, a Shab-related K+ channel isolated from rat brain, is insensitive to previously identified peptide inhibitors. We have isolated two peptides from the venom of a Chilean tarantula, G. spatulata, that inhibit the Kv2.1 K+ channel. The two peptides, hanatoxin1 (HaTx1) and hanatoxin2 (HaTx2) are unrelated in primary sequence to other K+ channel inhibitors. Th...