NR AGBT
AU Johnston,A.R.; Fraser,J.R.; Jeffrey,M.J.; MacLeod,N.
TI Synaptic plasticity in the CA1 area of the hippocampus of scrapie-infected mice
QU Neurobiology of Disease 1998 Sep; 5(3): 188-95
PT journal article
AB Using conventional in vitro extracellular field potential recordings we have investigated both short- and long-term synaptic plasticity in the hippocampal CA1 area of mice infected with ME7 scrapie. In agreement with earlier studies, no changes were seen in the properties of the Schaffer collateralevoked field excitatory postsynaptic potential during the early stages of the disease (up to 160 days, post inoculation, d.p.i) after which time the recorded potentials were seen to attenuate. Also, up to this time no changes were seen in either paired-pulse facilitation or post-tetanic potentiation, which are short-term phenomena associated with brief elevations in presynaptic calcium levels. However, there was a significant shift from the ability of slices to maintain long-term potentiation (LTP) from 100 d.p.i. onwards. In all of these experiments short-term potentiation (STP) was preserved, suggesting that from the time that abnormal PrP becomes detectable, or perhaps even earlier, the mechanisms responsible for stabilizing the maintenance phase of LTP are impaired. This result is discussed in terms of the relationship between STP and LTP and how this might be compromised by the conversion of cellular prion protein (PrPc) to the scrapie, protease resistant form of PrP (PrPsc).
MH Animal; Dendrites/chemistry/physiology; Disease Models, Animal; Excitatory Postsynaptic Potentials/physiology; Hippocampus/*physiology; Long-Term Potentiation/*physiology; Male; Mice; Mice, Inbred C57BL; Neuronal Plasticity/*physiology; Neurotransmitters/metabolism; Organ Culture; Prions/metabolism; Scrapie/*physiopathology; Support, Non-U.S. Gov't; Synapses/chemistry/metabolism
AD
Alex R. Johnston, Nikki MacLeod (nikki@ed.ac.uk), Department of Physiology, University Medical School, Teviot Place, Edinburgh, EH8 9AG, United Kingdom; Janet R. Fraser (janet.fraser@bbsrc.ac.uk), Institute for Animal Health, BBSRC and MRC, Neuropathogenesis Unit, Ogston Building, West Mains Road, Edinburgh EH9 3JF, Scotland, UK;
Martin J. Jeffrey (m.jeffrey@vla.maff.gov.uk), VLA Lasswade Veterinary Laboratory, Pentlands Science Park, Bush Loan, Penicuik, Edinburgh EH26 OPZ, Scotland, UK
SP englisch
PO USA