Anisomycin blocks the late phase of long-term potentiation in the dentate gyrus of freely moving rats

Brain Res Bull. 1984 Jul;13(1):39-42. doi: 10.1016/0361-9230(84)90005-4.


Freely moving rats, chronically implanted with stimulation electrodes in the medial entorhinal cortex and recording electrodes in the dentate gyrus, received two 400 micrograms intraventricular injections of anisomycin during a tetanization procedure that induced a long-lasting potentiation (72 hours) of the monosynaptic field potential. Inhibition of protein synthesis during the tetanization procedure did not immediately influence the induction of long-term potentiation (LTP). However, 3-4 hours after the beginning of tetanization the potentiation effect decayed progressively and was abolished totally during the remaining 7 day observation period. In control experiments anisomycin did not affect the slope of field EPSP's and produced a reversible depression of the population spike amplitude. These data indicate a relatively specific effect of the protein synthesis inhibitor on mechanisms involved in a late phase of LTP stabilization.

MeSH terms

  • Animals
  • Anisomycin / pharmacology*
  • Calcium / physiology
  • Depression, Chemical
  • Evoked Potentials / drug effects
  • Hippocampus / drug effects*
  • Hippocampus / physiology
  • Male
  • Nerve Tissue Proteins / physiology
  • Pyrrolidines / pharmacology*
  • Rats
  • Rats, Inbred Strains
  • Synaptic Transmission / drug effects


  • Nerve Tissue Proteins
  • Pyrrolidines
  • Anisomycin
  • Calcium