Figure 2.

The antagonist Zn²⁺ exhibits appropriate selectivity at concatemeric receptors. (A–C) Representative responses of the indicated subunit combinations to a high GABA concentration in the absence and presence of Zn²⁺ (1 µM). (D) Summary data (n= 4–8 oocytes per subunit combination) for Zn²⁺ sensitivity under the conditions depicted in A–C. As expected Zn²⁺ sensitivity was highest in receptors with no auxiliary subunit and was intermediate at α4/δ-containing concatemers. *P < 0.05, significantly different from each of the other two values; two-tailed unpaired t-test.