Figure 8. PCCP⁻ prevents the increase in PCCP⁻ sensitivity of α₁V256β₂γ₂ mediated by MTSET⁺ + GABA.

GABA (EC₁₀) was applied repetitively until a stable current response was observed followed by inhibition of the channel by PCCP⁻. Subsequently 5 mM MTSET was applied in the presence of GABA. After MTSET⁺ treatment GABA was applied twice followed by a combined application of GABA and the same concentration of PCCP⁻ used before. A, Wild type receptors were not affected by this treatment. B, The treatment leads to an enhanced inhibition in α₁V256Cβ₂γ₂. C, 5 mM MTSET⁺ was applied to α₁V256C mutant receptor in presence of GABA and 1 mM PCCP⁻. PCCP⁻ prevented enhanced inhibition and therefore covalent reaction. These experiments were repeated independently three times using different oocytes.