Summary
The distribution of radioactivity at branches and terminals of the fast axon in extensor tibiae muscle incubated in the radiolabelled putative neurotransmitter L-glutamate was determined by electron microscopic autoradiography. Quantitative analysis of the distribution of silver grains at the axon branches and terminals in preparations stimulated at a low frequency shows that most of the radioactivity is present in the glial cells. In preparations stimulated to the point of fatigue substantial radioactivity is present in both the glial cells and the axoplasm of the terminals. It is suggested that the uptake of L-glutamate into the axoplasm of the terminals is correlated with the depletion and recovery of vesicle numbers after stimulation.
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The authors thank Dr. N.M. Blackett for running the computer analyses of the autoradiographical data. R.P. Botham gratefully acknowledges the SRC for financial assistance
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Botham, R.P., Beadle, D.J., Hart, R.J. et al. Glutamate uptake after stimulation-induced depletion of vesicle numbers in neuromuscular junctions of Locusta migratoria L.. Cell Tissue Res. 203, 379–386 (1979). https://doi.org/10.1007/BF00233267
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DOI: https://doi.org/10.1007/BF00233267