Accession Number : ADA033405


Title :   Effect of Curare on Responses to Different Putative Neurotransmitters in Aplysia.


Descriptive Note : Scientific rept.,


Corporate Author : ARMED FORCES RADIOBIOLOGY RESEARCH INST BETHESDA MD


Personal Author(s) : Carpenter,D. O. ; Swann,J. W. ; Yarowsky,P. J. ; Myers,P. R. ; Willis,J. A.


Report Date : JUN 1976


Pagination or Media Count : 33


Abstract : The effects of curare on responses resulting from ionophoretic application of several putative neurotransmitters onto Aplysia neurons were studied. These neurons have specific receptors for acetylcholine (ACh), dopamine, octopamine, phenylethanolamine, histamine, gamma-aminobutyric acid (GABA), aspartic acid, and glutamic acid. Each of these substances may on different specific neurons elicit several types of response. Fast depolarizing Na and hyperpolarizing Cl conductance increase responses have been found for all of these putative transmitters and a slow hyperpolarizing K conductance increase response has been found for most. All responses resulting from either Na or Cl conductance increases, irrespective of which putative transmitter activated the response, were sensitive to curare. GABA responses were less sensitive and were often only depressed by .001 M curare. K conductance responses, irrespective of the transmitter, were not curare sensitive. These results are consistent with a model of receptor organization in which one neurotransmitter receptor may be assoicated with any of at least three ionophores, mediating conductance increase responses to Na, Cl and K, respectively. In Aplysia nervous tissue, curare appears to be a specfic blocking agent for a class of receptor-activated Na and Cl responses.


Descriptors :   *ACETYLCHOLINE, *CHEMORECEPTORS, *CURARE ALKALOIDS, MODELS, AMINES, PHYSIOLOGICAL EFFECTS, CHLORIDES, NERVE CELLS, ELECTROLYTES, VENOMS, DOPAMINE, AMINO ACIDS, NEUROCHEMICAL TRANSMISSION.


Subject Categories : BIOCHEMISRTY


Distribution Statement : APPROVED FOR PUBLIC RELEASE