Differential release of D-[3H]aspartate and [14C]gamma-aminobutyric acid following activation of commissural fibres in a longitudinal slice preparation of guinea pig hippocampus.
Low-stimulus frequencies released both D-[3H]aspartate and [14C]GABA in double labelling experiments after activation of the commissural fibres to stratum oriens in hippocampal slices. The stimulus-dependent release of [14C]GABA was highest at low stimulus frequencies (10 Hz) whereas at higher stimulus frequencies (30--50 Hz) it was almost abolished. All stimulus frequencies used released D-[3H]aspartate. The results indicate that activation of the commissural fibres in stratum oriens, using low stimulus frequencies, activates pyramidal cells which stimulate inhibitory neurones releasing GABA as a transmitter.
D000818:Animals; D001224:Aspartic Acid / Q000378:metabolism*; D004558:Electric Stimulation; D006168:Guinea Pigs; D006624:Hippocampus / Q000378:metabolism*; D066298:In Vitro Techniques; D009412:Nerve Fibers / Q000502:physiology*; D009433:Neural Inhibition; D009435:Synaptic Transmission; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D001224:Aspartic Acid; D005680:gamma-Aminobutyric Acid