Fig. 6. Absence of morphologic alterations produced by long-term treatment of slice cultures with 100 μg/ml propofol. (A ) Toluidine blue–stained semithin section of the CA1 region of a control hippocampal slice culture. (B ) Same as in (A ) but after 10 days of treatment with 100 μg/ml propofol. (C ) Typical symmetric inhibitory synapse on a CA1 pyramidal cell body of a propofol-treated culture (bar: 10 μm).