[Effect of long-term administration of haloperidol: ultrastructural changes in the prefrontal cortex]

Haloperidol, when injected regularly during 3 weeks at a dose of 0.1 mg/kg, influenced glial cells and neuropile. The conditions of the glial cells suggested their increased metabolism. Morphometry revealed increased density of axodendritic synapses and reduced density of axospinal synapses at the spinal collumin the IV layer of medial prefrontal cortex. Virtually all the parameters measured in axodendritic synapses were decreased (presynaptic terminal area, mytochondrial total area and their count in the presynaptic terminal, the length of postsynaptic dense area). The data indicate that ultrastructural changes resulted from decrease of efficiency of synaptic transmission which occurred in several synapses as a result of haloperidol induced receptor block.