Abstract:
:Associative memory of the mollusc Hermissenda crassicornis, previously correlated with changes of specific K+ currents, protein phosphorylation, and increased synthesis of mRNA and specific proteins, is here shown to be accompanied by macroscopic alteration in the structure of a single identified neuron, the medial type B photoreceptor cell. Four to five days after training, terminal arborizations of B cells iontophoretically injected with Ni2+ ions and then treated with rubeanic acid were measured with charge-coupled device (CCD)-digitized pseudocolor images of optical sections under "blind" conditions. Boundary volumes enclosing medial-type B-cell arborizations from classically conditioned animals were unequivocally reduced compared with volumes for naive animals or those trained with unpaired stimuli. Branch volume magnitude was correlated with input resistance of the medial type B-cell soma. Such associative learning-induced structural changes may share function with "synapse elimination" described in developmental contexts.
journal_name
Proc Natl Acad Sci U S Aauthors
Alkon DL,Ikeno H,Dworkin J,McPhie DL,Olds JL,Lederhendler I,Matzel L,Schreurs BG,Kuzirian A,Collin Cdoi
10.1073/pnas.87.4.1611subject
Has Abstract,Author List Incompletepub_date
1990-02-01 00:00:00pages
1611-4issue
4eissn
0027-8424issn
1091-6490journal_volume
87pub_type
杂志文章abstract::The specific ornithine decarboxylase inhibitor alpha-difluoromethylornithine, when given to adult rats in vivo for 5 wk, resulted in a decrease in peripheral blood cell elements in normal rats and a marked suppression of marrow recovery in rats with chemotherapy-induced marrow hypoplasia. In normal rats, alpha-difluor...
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