Identification of a GABA-containing cerebral-buccal interneuron-11 in Aplysia californica.
The cerebral-buccal interneurons (CBIs) in Aplysia are a group of inter-ganglionic projection neurons that regulate feeding motor programs. In this study, electrophysiological and immunocytological methods were used to identify a previously uncharacterized CBI, designated CBI-11. CBI-11 is a gamma-aminobutyric acid (GABA)-immunoreactive neuron located in the G cluster of the cerebral ganglion. Firing CBI-11 produced fast picrotoxin-sensitive inhibitory postsynaptic potentials (IPSPs) in buccal motor neuron B3. Local application of GABA to B3 produced a picrotoxin-sensitive hyperpolarization that reversed at the same membrane potential as the IPSPs elicited by stimulation of CBI-11. Together, these observations indicate that CBI-11 utilizes GABA as its transmitter. Finally, stimulation of CBI-11 elicited rhythmic motor programs in quiescent buccal ganglia. Thus, CBI-11 is a GABAergic CBI that can function as a motor program initiator.
Wu
Jin-Sheng
JS
Center for Neurobiology and Behavior, New York State Psychiatric Institute and College of Physicians and Surgeons of Columbia University, New York, NY 10032, USA.
Jing
Jian
J
Díaz-Ríos
Manuel
M
Miller
Mark W
MW
Kupfermann
Irving
I
Weiss
Klaudiusz R
KR
D000818:Animals; D001048:Aplysia / Q000187:drug effects / Q000502:physiology*; D017952:Ganglia, Invertebrate / Q000737:chemistry / Q000187:drug effects / Q000502:physiology*; D007395:Interneurons / Q000737:chemistry / Q000187:drug effects / Q000502:physiology*; D009061:Mouth Mucosa / Q000737:chemistry / Q000187:drug effects / Q000502:physiology*; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000032:analysis / Q000502:physiology*
D005680:gamma-Aminobutyric Acid