“Tacrine (1,2,3,4-tetrahydro-9-acridinamine) inhibited binding of [3H]flunitrazepam to benzodiazepine receptors of guinea … an inhibition constant of 46 microM at 2 degrees C and 37 degrees C. gamma-Aminobutyric acid GABA ) decreased … of tacrine for the receptor, suggesting that … act as an inverse agonist.”