Chronological Alteration of Calbindin D-28k and Calretinin Immunoreactivity in the Gerbil Trigeminal Ganglion After Ischemia-Reperfusion / 대한해부학회지

ABSTRACT

Many researches have focused upon temporal changes of neurotransmitters and/or neuromodulators in the central nervous system after ischemic insult. In sensory neurons, the spatial and temporal alterations of neurotransmitters have been little studied. Calbindin D-28k (CB) and calretinin (CR) have been suggested to play a role in the transmission of neurotransmitters. Therefore, in the present study we investigated the chronological alteration of CB and CR immunoreactivity in the trigeminal ganglion cells of the Mongolian gerbil after ischemic insult. In the sham operated group, CB and CR immunoreactivities were found in small -, medium -and large -sized neurons. One and two days after ischemia-reperfusion, small and large-sized CB immunoreactive neurons increased significantly. Thereafter, number of the CB immunoreactive neurons decreased markedly. Furthermore, five days after ischemia -reperfusion, CB immunoreactivity was detected in a few neurons, and its immunoreactivity was also very weak in the cytoplasm. Number of the large -sized CR immunoreactive neurons increased significantly one day after ischemia -reperfusion. Thereafter, the number of the large -sized CR immunoreactive neurons decreased. Especially, the number of the medium-sized CR immunoreactive neurons increased dramatically 4 days after ischemia-reperfusion. These results suggest that an increase of CB and CR may play an important role in modulating the mechanoception 1 day after ischemia-reperfusion, because the immunoreactivities increased in large -sized neurons which have the myenlinated A fibers. These results also suggest that significant increase of CR expression in medium -sized neurons 4 and 5 days after ischemia-reperfusion may provoke CR in modulating the nociception or thermoception because the medium-sized neurons which have the myenlinated A sigma or C fibers.