Publication Type: | Journal Article |
Year of Publication: | 1988 |
Authors: | J. M. Schaeffer, Bergstrom A. R. |
Journal: | Life Sciences |
Volume: | 43 |
Pagination: | 1701-1706 |
Date Published: | 1988 |
ISBN Number: | 0024-3205 |
Keywords: | Caenorhabditis elegans (Nematoda)., Caenorhabditis elegans [Neurotransmitter receptors / / GABA binding, concentration & possible function]., GABA identification, Nervous system, properties & implications for function] [Neurotransmitters / /, sites |
Abstract: | Gamma-aminobutyric acid (GABA), glutamate decarboxylase and GABA-transaminase were identified in the nematode Caenorhabditis elegans. The concentration of GABA in C. elegans (0.14 .mu.g/mg protein) is approximately 10-fold lower than the concentration of GABA in rat brain. Glutamate decarboxylase and GABA-transaminase, the GABA anabolic and catabolic enzymes, are also present in C. elegans. Crude membrane fractions were prepared from C. elegans and used to study specific [3H] GABA binding sites. GABA binds to C. elegans membranes with high affinity (37 nM) and low capacity (Bmax = 2.25 pmol/mg protein). Muscimol is a competitive inhibitor of specific GABA binding with a KI value of 120 nM. None of the other GABA agonists or antagonists inhibited greater than 40% of the specific GABA binding at concentrations up to 10-4M. Thirteen spider venoms were examined as possible GABA agonists or antagonists, the venom from Calilena agelenidae inhibits specific GABA binding with a KI value of 6 nl/ml. These results suggest that GABA has a physiological role as a neurotransmitter in C. elegans. |
URL: | <Go to ISI>://ZOOREC:ZOOR12500028329 |