T-type calcium channels regulate cortical plasticity in-vivo. [corrected].

T-type voltage-dependent calcium channels may play an important role in synaptic plasticity, but lack of specific antagonists has hampered investigation into this possible function. We investigated the role of the T-type channel in a canonical model of in-vivo cortical plasticity triggered by monocular deprivation. We identified a compound (TTA-I1) with subnanomolar potency in standard voltage clamp assays and high selectivity for the T-type channel. When infused intracortically, TTA-I1 reduced cortical plasticity triggered by monocular deprivation while preserving normal visual response properties. These results show that the T-type calcium channel plays a central role in cortical plasticity.