GABA-induced synaptic facilitation at type B to A photoreceptor connections in Hermissenda.
Gamma-aminobutyric acid (GABA) is a prevalent neurotransmitter in both vertebrate and invertebrate systems. Here we report that, in addition to its usual inhibitory actions, GABA induced synaptic facilitation at type B to A photoreceptor connections of the marine mollusk Hermissenda when applied transiently to the isolated nervous system. Synaptic facilitation also occurred in response to mechanical stimulation of the GABAergic hair cells, which are normally activated by rotational unconditioned stimuli during behavioral training of the intact animal. This synaptic facilitation represents a novel form of GABA-induced neuromodulation which may contribute to learning-dependent suppression of phototaxis in Hermissenda.
Schultz
L M
LM
Department of Psychology, Princeton University, NJ 08544, USA.
Clark
G A
GA
D000200:Action Potentials / Q000187:drug effects; D000818:Animals; D004558:Electric Stimulation; D006198:Hair Cells, Auditory / Q000502:physiology; D066298:In Vitro Techniques; D008974:Mollusca; D017956:Photoreceptor Cells, Invertebrate / Q000187:drug effects / Q000502:physiology*; D010812:Physical Stimulation; D013569:Synapses / Q000187:drug effects / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects*; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology*
D005680:gamma-Aminobutyric Acid