Aim: To explore the neuronal circuit and possible pathway related to the 5-HT3 receptors in hippocampus neuroimmunomodulation.
Methods: SABC immunocytochemical staining was used to detect the c-fos expression.
Results: A large number of FOS-positive neurons expression were found in the hippocampus and brain cortex at 1 hour after microinjection of 5-HT3 receptor agonist (I-PBG) in the hippocampus, but as time went on, the number of FOS positive-neurons gradually decrease. A small number of FOS positive-neurons were found only in the hypothalamus and gray matter around acqueduct of midbrain, respectively at 8 and 16 hs after injection of 1-PBG. The expression of c-fos induced by 1-PBG could be blocked by pre-microinjection of tropisetron.
Conclusion: Brain cortex-hippocampus hypothalamus-gray matter around acqueduct of midbrain forma neuronal network, which may be related to immunomodulation.