title: Chicks injected with antisera to either S-100 alpha or S-100 beta protein develop amnesia for a passive avoidance task.
abstract: The cellular expression of S-100 beta protein is upregulated in Alzheimer's disease and in Down's syndrome, and this protein has been implicated in memory-related processes in laboratory animals. However, the possibility that the alpha subunit of S-100 is also involved in memory has not yet been examined. In the present study, day-old black Australorp white Leghorn cockerel chicks (Gallus domesticus) received injections of monoclonal antisera to S-100 alpha (1:50) or S-100 beta (1:500) into each hemisphere immediately after training on a one-trial passive avoidance task. The chicks displayed significantly lower retention levels than control birds that had been injected with antisera to carbonic anhydrase, or with saline (p < .01). S-100 alpha antisera had an amnestic effect when injected between 0 and 20 min after training, with memory deficits occurring from 30 min post-learning, at the point of transition between the A and the B phases of the Gibbs-Ng intermediate memory stage. By contrast, the S-100 beta antisera needed to be injected either 5 min before or immediately after training and produced amnesia 10 min earlier, at the start of the A phase of the intermediate memory stage. We conclude that the two subunits of the S-100 protein are required at different points in the sequence of events leading to the consolidation of passive avoidance memory.
authors.affiliation: Department of Physiology and Pharmacology, University of Queensland, Brisbane, Australia. b.odowd@vthrc.uq.edu.au
authors.forename: B S
authors.initials: BS
authors.lastname: O'Dowd
authors.forename: W Q
authors.initials: WQ
authors.lastname: Zhao
authors.forename: K T
authors.initials: KT
authors.lastname: Ng
authors.forename: S R
authors.initials: SR
authors.lastname: Robinson
mesh_terms: D000647:Amnesia / Q000139:chemically induced*; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects*; D001522:Behavior, Animal; D002645:Chickens; D004305:Dose-Response Relationship, Drug; D007106:Immune Sera; D008568:Memory / Q000187:drug effects; D009418:S100 Proteins / Q000009:adverse effects* / Q000494:pharmacology
chemical_list: D007106:Immune Sera; D009418:S100 Proteins