Effect of intraventricular injection of histamine on corticotropin releasing hormone neurons in paraventricular nucleus of hypothalamus

AIM:To study the effect of intraventricular injection(icv) of histamine(HA) on corticotropin releasing hormone (CRH) neurons activity in paraventricular nucleus (PVN) of hypothalamus. METHOD: Fos ontogenic protein immunohistochemistry and double antigen immunohistochemistry method; semiquantitative reverse transcription-polymerase chain reaction(RT-PCR) method were used. RESULTS: After intraventricular injection of HA, (1) number of Fos immunnoreactive positive neurons in PVN increased significantly; (2) double labeling experiments showed that there were 31 78%±1 59% of Fos immunoreactive cells in PVN expressed CRH simultaneously; (3) the CRHmRNA level in PVN was increased in a dose-dependent manner. CONCLUSION: Central histamine activated CRH neurons in PVN of hypothalamus and increase the expression of CRH gene.