These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: High rates of excitatory miniature currents in crayfish claw opener muscle evoked by high concentrations of gamma-aminobutyric acid (GABA) in normal and Ca2+-deficient superfusions.
    Author: Finger W.
    Journal: Neurosci Lett; 1984 Jun 29; 47(3):251-6. PubMed ID: 6089041.
    Abstract:
    High concentrations (0.5 mol/l) of the neutral amino acid GABA were used to evoke release of transmitter quanta from excitatory terminals at voltage clamped crayfish muscle fibres in normal and Ca2+-deficient superfusions. An experiment in which the release of transmitter quanta proceeded at high rates in both normal and Ca2+-deficient superfusion was analyzed in detail indicating a Ca2+-independent mechanism of release. In the normal superfusion, on application of GABA, the release rates ñ increased within a few seconds up to about 6000 quanta/s and thereafter declined exponentially with a time constant tau q = 18.5 s, most likely due to depletion of a readily releasable store of transmitter in the excitatory nerve terminals comprising at least 110,000 quanta per muscle fibre. Assuming that about 1900 excitatory synapses exist per muscle fibre [9], it results that about 58 quanta can be associated with each synapse in agreement with morphological data [15] which show that between 47-117 vesicles exist in a single glutamatergic synapse of crayfish.
    [Abstract] [Full Text] [Related] [New Search]