Single-prolonged stress induce changes of CaM/CaMKIIα in the rats of dorsal raphe nucleus.

Ca2+/calmodulin-dependent protein kinase IIα (CaMKIIα) is identified as a Ca2+-dependent kinase in brain involved in the activation of Tryptophan hydroxylase (TPH) acting through direct phosphorylation of TPH, and playing key roles in the signaling pathways initiated by various G protein-coupled 5-HT receptors. The goal of this study is to detect whether there are changes of CaM and CaMKIIα in dorsal raphe nucleus in the rats exposed to single-prolonged stress (SPS), which is a model employed in post-traumatic stress disorder (PTSD) study extensively. A total of 90 male Wistar rats were randomly divided into a normal control group and SPS groups of 7d, 14d. The changes of CaM/CaMKIIα were detected by immunohistochemistry, reverse transcription-polymerase chain reaction and western blot. Our results demonstrate that both expressions of CaM and CaMKIIα significantly increase (P < 0.001) in the SPS 7d group than that in the control group, and then decreased dramatically (P < 0.001) 14 days after SPS. Our results confirm that SPS induce changes of CaM/CaMKIIα in the dorsal raphe nucleus. Changes of CaM/CaMKIIα may be associated with the activation of 5-HT1A receptor, and may contribute to the progress of molecular mechanism of PTSD.