Which drug acts through alpha subunit of GABA receptor?

Benzodiazepine acts at alpha unit of GABA receptor predominately, barbiturates acts at other sites The chloride channel is gated by the primary ligand GABA. The benzodiazepine (BZD) receptor modulates GABAA receptor in either direction: agonists like diazepam facilitate, while inverse agonists like DMCM hinder GABA mediated Cl- channel opening and BZD antagonist flumazenil blocks the action of both. The barbiturate receptor, located elsewhere, also facilitates GABA and is capable of opening Cl- channel directly as well. Bicuculline blocks GABAA receptor, while picrotoxin blocks the Cl-channel directly. Ref: katzung 12th ed.