Abstract
The expression of NGF and its tyrosine kinase receptor, trk A in the trigeminal motor nucleus, the facial nucleus, the hypoglossal nucleus and the nucleus ambiguus of the rat was investigated by immunohistochemical methods. In adult rats, the immunoreactivities of NGF and trk A in all nuclei examined were detected. The expression of them in suckling animals was also examined and the immunoreactivities of them were detected at postnatal day 5 weakly. This result and our previous results about the expression of other neurotrophins suggested that various neurotrophins might play roles in the survival and/or regulation of the motoneurons involved in eating and swallowing.
