Chondroitin Sulfate Induces Depression of Synaptic Transmission and Modulation of Neuronal Plasticity in Rat Hippocampal Slices
Chondroitin sulfate (CS) reversibly depresses synaptic transmission in the hippocampal slice. (a) Time-course of fEPSP slope depression exerted by CS (300 μM) applied during the time indicated by the top horizontal bar. Every dot represents the minute-averaged fEPSP slope. Note the fast turn-on and turn-off of effects exerted by CS. Insets A and B represent the original traces of fEPSPs in the points A and B of the time-course curve. (b) Degree of depression caused by each concentration of CS at the end of 20 min of perfusion. A single concentration of CS per slice was tested. Data were fitted to the concentration-response curve. Data represent the mean ± SEM ( to 8 slices). (c) Time-course of fEPSP slope in the dentate gyrus measured before, during, and after CS applied during 60 min (top horizontal bar). Inset, original traces taken from points A and B of the time-course curve. (d) Time-course of changes on fibber volley (FV) amplitude induced by bath application of 300 μM CS for the time indicated by the top horizontal bars. Data were normalized to the mean value of the control period and expressed as mean ± SEM/min of 8–13 experiments.