Benzodiazepine receptor involvement in the control of receptive field size and responsiveness in primary somatosensory cortex.
Microiontophoretic ejection of 3 benzodiazepines (BZDs), flurazepam, diazepam and midazolam, and of Ro 15-1788 to primary somatosensory cortical neurons altered the nature of the responses evoked by natural stimulation of the cutaneous surface. BZDs raised the thresholds to tactile stimulation and produced a decrease of the receptive field areas of neurons situated in rapidly adapting submodality regions of S1 cortex; these effects of the BZDs were exerted at different apparent potencies. Ro 15-1788 antagonized the BZD-induced receptive field size decreases and threshold changes. When administered alone, this substance sometimes lowered the threshold for tactile activation and slightly enlarged the receptive field size.
D000818:Animals; D001569:Benzodiazepines / Q000494:pharmacology; D001570:Benzodiazepinones / Q000494:pharmacology; D002415:Cats; D003975:Diazepam / Q000494:pharmacology; D005260:Female; D005442:Flumazenil; D005479:Flurazepam / Q000494:pharmacology; D008297:Male; D008874:Midazolam; D009474:Neurons / Q000187:drug effects; D011963:Receptors, GABA-A / Q000502:physiology*; D012684:Sensory Thresholds / Q000187:drug effects; D013003:Somatosensory Cortex / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D014110:Touch / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D001570:Benzodiazepinones; D011963:Receptors, GABA-A; D001569:Benzodiazepines; D005442:Flumazenil; D005680:gamma-Aminobutyric Acid; D005479:Flurazepam; D003975:Diazepam; D008874:Midazolam