The Proto-Osmotic Mechanism of Muscular Contraction

FIGURE 2. Proton and K fluxes for a pair of thin filaments and a thick filament. Only one cross-bridge has been shown. In the lower part of the diagram the loop flow of the K layer has been indicated. 

The equations for the fluxes of and and the expression for the diffusion potential will be derived now for a filament on the basis of the assumptions discussed in Section 2.2. Across the length / of the proton-con-ducting filament a chemical potential difference FKh= —i Tln Ch(/)/ch(0) is assumed to be maintained by two synchronized chemical reactions which inject and take out H at z = 0 and z = 1 respectively. The K layer has the radial extension from r = ator = a-ft/ with the thickness d corresponding roughly to the Debye length. The concentration of in the K layer will 

Fk = — RT/F) In Ck(/)/ck(0)- The expression for the diffusion potential difference V follows from the condition of the conservation of electroneutrality applied to the restricted volume confined by the surface r = a + d, which gives J = —/r- Hence 

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