Unusual effects of benzodiazepines and cyclodiene insecticides on an expressed invertebrate GABAA receptor

FEBS Lett. 1992 Aug 3;307(3):351-4. doi: 10.1016/0014-5793(92)80711-o.


We have previously reported [(1991) EMBO J. 10, 3239-3245] the sequence of an invertebrate gamma-aminobutyric acid (GABA) type A (GABAA) receptor polypeptide which forms homo-oligomeric GABA-gated, bicuculline-sensitive, chloride-ion channels upon heterologous expression. We now demonstrate that the benzodiazepines Ro5-4864 (4'-chlorodiazepam) and diazepam, that are active at mammalian peripheral benzodiazepine sites, and not those benzodiazepines specific for central sites, directly active the homo-oligomeric receptor and evoke larger maximal responses than those elicited by GABA. In addition, members of the cyclodiene class of insecticides block the channel of the receptor in a manner indistinguishable from that of picrotoxin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Benzodiazepines / pharmacology*
  • Benzodiazepinones / pharmacology
  • Diazepam / pharmacology
  • Endrin / pharmacology
  • Heptachlor Epoxide / pharmacology
  • Insecticides / pharmacology*
  • Lymnaea
  • Picrotoxin / pharmacology
  • RNA / genetics
  • Receptors, GABA-A / drug effects*
  • Receptors, GABA-A / genetics
  • Transcription, Genetic


  • Benzodiazepinones
  • Insecticides
  • Receptors, GABA-A
  • Heptachlor Epoxide
  • Picrotoxin
  • Benzodiazepines
  • 4'-chlorodiazepam
  • RNA
  • Endrin
  • Diazepam