Membrane potential changes induced by gamma-aminobutyric acid and related amino acids in the rabbit superior cervical ganglion.
The effects of gamma-aminobutyric acid (GABA), delta-aminolaevulinic acid (DALA) and delta-aminovaleric acid(DAVA) on membrane potential were studied in the isolated rabbit superior cervical ganglion (SCG) using external electrodes(sucrose-gap apparatus). GABA(5.2-1031 micrograms), DALA(335-1676 micrograms), and DAVA(206.2-1563 micrograms) produced a dose-dependent depolarization in the rabbit SCG. The mean (+/- SEM) ED 50s for the depolarizations produced by GABA, DALA, and DAVA were 58.8 +/- 2.2 micrograms, 733 +/- 16.1 micrograms, and 845 +/- 12.9 micrograms, n = 6, respectively. The mean (+/- SEM) maximum depolarizations were: 1.4 +/- 0.12 mV, 0.91 +/- 0.1 mV, and 0.95 +/- 0.1 mV, n = 6, respectively. It is concluded that GABA and the related aminoacids produce depolarizations in the rabbit SCG, which are similar in shape and duration but larger in amplitude than those produced in the rat SCG.
D000596:Amino Acids / Q000494:pharmacology*; D021542:Amino Acids, Neutral; D000622:Aminolevulinic Acid / Q000494:pharmacology; D000818:Animals; D005260:Female; D005728:Ganglia, Sympathetic / Q000187:drug effects*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D011817:Rabbits; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology*
D000596:Amino Acids; D021542:Amino Acids, Neutral; D005680:gamma-Aminobutyric Acid; C013809:5-aminovaleric acid; D000622:Aminolevulinic Acid