title: Calcium and unit response decrement to locally applied glutamate on rat hippocampal CA1 neurons.
abstract: In rat hippocampal slices, sensitivity of CA1 neuronal somata to iontophoretically applied glutamate pulses was reduced subsequent to: (1) a 20 Hz tetanic stimulation of stratum radiatum; (2) an application of N-methyl-DL-aspartate or glutamate or Ca2+. This decreased responsiveness was sometimes followed by an increase. Ca2+ antagonists, verapamil and Mn2+, interfered with the induction of the above changes in sensitivity to glutamate pulses. No correlation was observed between alterations in sensitivity of these neurons to glutamate and changes in synaptically-induced responses. These results suggest that a build-up of CA1 cell Ca2+ could be involved in decreasing the responsiveness (desensitization of receptors?) of the neuron to applied glutamate leading to a compensatory increase in the sensitivity.
authors.forename: P
authors.initials: P
authors.lastname: Murali Mohan
authors.forename: B R
authors.initials: BR
authors.lastname: Sastry
mesh_terms: D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D005071:Evoked Potentials / Q000187:drug effects; D005971:Glutamates / Q000494:pharmacology*; D018698:Glutamic Acid; D006624:Hippocampus / Q000187:drug effects* / Q000502:physiology; D066298:In Vitro Techniques; D007478:Iontophoresis; D008297:Male; D016202:N-Methylaspartate; D009474:Neurons / Q000187:drug effects / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D005971:Glutamates; D001224:Aspartic Acid; D018698:Glutamic Acid; D016202:N-Methylaspartate; D002118:Calcium