In vitro release of endogenous beta-alanine, GABA, and glutamate, and electrophysiological effect of beta-alanine in pigeon optic tectum.
The efflux of 20 amino acids, induced by either high K+ concentration or veratrine, was determined in pigeon tectal slices. Ca2+-dependent, K+-induced release of beta-alanine, gamma-aminobutyric acid (GABA), and glutamate was observed. Veratrine caused release of the same amino acids plus glycine in a tetrodotoxin-sensitive manner. beta-Alanine had a strong inhibitory effect on the activity of tectal neurons which was blocked by strychnine but not by bicuculline. The results indicated a transmitter function for beta-alanine in the optic tectum, and were consistent with the previously proposed transmitter role of GABA and glutamate in this structure.
D000409:Alanine / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D010856:Columbidae / Q000502:physiology*; D004594:Electrophysiology; D005971:Glutamates / Q000378:metabolism*; D018698:Glutamic Acid; D011188:Potassium / Q000494:pharmacology; D013331:Strychnine / Q000494:pharmacology; D013477:Superior Colliculi / Q000187:drug effects / Q000502:physiology*; D013779:Tetrodotoxin / Q000494:pharmacology; D014702:Veratrine / Q000494:pharmacology; D015091:beta-Alanine / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism*
D005971:Glutamates; D015091:beta-Alanine; D018698:Glutamic Acid; D013779:Tetrodotoxin; D005680:gamma-Aminobutyric Acid; D014702:Veratrine; D013331:Strychnine; D000409:Alanine; D011188:Potassium; D002118:Calcium