Size of hippocampal pyramidal neurons in schizophrenia

Background Meta-analyses of hippocampal size have indicated that this structure is smaller in schizophrenia. This could reflect a reduction in the size of constituent neurons or a reduced number of neurons. Aims To measure the size of hippocampal pyramidal neurons in the brains of people with and without schizophrenia. Method Pyramidal neuron size in hippocampal subfields was estimated stereologically from sections taken at 5 mm intervals throughout the whole length of right and left hippocampi from the brains of 13 people with schizophrenia and 16 controls. Results were assessed using repeated-measures analysis of covariance looking for a main effect of diagnosis and gender, and interactions of these with side. Results We were unable to detect significant differences related to diagnosis, gender or side for any hippocampal subfield for this series of cases. Conclusions For this series of brains, hippocampal cell size is unchanged in schizophrenia.