Projections From The Parvicellular Reticular Nucleus In The Facilitation Section Of The Rat Medulla Oblongata

Parvicellular reticular nucleus(PCRt) had the faction that regulated mouth facial movements,such as breathing,phonating,chewing,swallowing,et al.At the same time,it accepted downlink projections from the central nervous system and the sensory signals from peripheroceptor.It was the relay station of proprioceptive signals induced by the mouth facial motor neuron reflex activities.In recent years,we found that not only four limbs' muscle tensity had a substantial decline in children with spastic cerebral palsy undergoing SDR,but also the incidental symptom of salivation had been improved in different degree.It prompted that there was a fibrous relationship between parvicellular reticular nucleus and nucleus in the rat brainstem that control swallowing and gland secretion.But the present domestic aspect's research dates were rare.The experiment mainly observed by morphology fibrous connection between this nuclear group and nucleus in the rat brainstem that control swallowing and gland secretion,as well as further understands that fiber project from parvicellular reticular nucleus in reticular formation in brain stem to ceivial medullaris.Methods1.Earbon ink was unilaterall injected into PCRt of the adult rats by microtransfusing and the sections were made HE dyeing,then it was observed the place injected of PCRt was accurate or not.2.By means of the injection of a small amount of wheat germ agglutinin-horseradish peroxides(WGA-HRP) into one side of PCRt in the adult rats,according to the way of TMB-ST,the staining was displayed,and then we watched the place that was injected and tagged in the sections through light microscope.3.The one side of PCRt of the adult rats was transfused into 1,l'-dioctadecyl-3,3, 3',3'-tetramethy-lindocarbocyanine perchlorate(DiI),and then,brain tissue was taken out and sections were observed using fluorescence microscope.Result1.The antegradely labeled fibers were found in hypoglossal nucleus,dorsal motor nucleus of vagus,facial nerve nucleus,ambiguous nucleus,superior salivatory nucleus,inferior salivatory nucleus,spinal trigeminal nucleus and motor trigeminal nucleus.It was contralateral preponderant.The antegradely labeled fibers and retrogradely labeled nerve cells were observed in solitary tract nucleus,medial ventral nucleus,contralateral preponderantly.2.The antegradely labeled fibers were found in laminaâ… ,â…¡and labeled nerve cells retrogradely,labeled nerve fibers in laminaâ…¦,â…§of cervical spinal cord.3.The distribution labeled through WGA-HRP was close to DiI;however,the difference of them was anything labeled by DiI was not seen in inferior salivatory nucleus.The number of fibers and nerve cells marked with DiI was less than WGA-HRP as a tracer.Conclusion1.By observing the tracer of WGA-HRP and DiI,it indicates that there's a direct relationship between parvicellular reticular nucleus and motor nucleus in the rat brainstem and cervical spinal cord nucleus.2.The parvicellular reticular nucleus project nerve fibers to laminaâ… ,â…¡of cervical spinal cord and receive nerve fibers projection from neurons in laminaâ…¦,â…§of cervical spinal cord.