THE ROLE OF INHIBITION IN DENTATE GATEKEEPER FUNCTION: VOLTAGE - SENSITIVE DYE IMAGING STUDY

초록

Granule cells of the dentate gyrus (DG) are very resistant to firing multiple action potentials in response to perforant path (PP) stimulation. This has led to the idea that the DG acts as a gatekeeper to the hippocampus through the effective recruitment of inhibition onto DG granule cells. To examine this, we look at the ability of the DG to suppress it own output into the hippocampus by imaging DG and CA3 activity and comparing their responses to PP stimulation. To do this, we used a 6400 pixel CCD camera running at 0.2 to 2 kHz and recorded changes in the fluorescence of the voltage sensitive dye RH-795. Adult rat hippocampal-entorhinal cortex slices were stained and placed in an interface chamber for imaging. A bipolar electrode was used to stimulate the PP.