RESUMO
The trigemino-cerebellar projections of rats were studied by introducing HRP microelectrophoretically into various areas of the cerebellar cortex. The results indicate that the following parts of the cerebellum receive bilateral (mostly ipsilateral) trigeminal projections, namely, the simple lobule, the crusa Ⅰ and Ⅱ, the paramedian lobuIe, the dorsal paraflocculus, the lateral part of the lobule Ⅷ and the vermal cortex of the lobules Ⅵ～Ⅸ.Fibers from the interpolar subnucleus and the principal sensory nucleus of the trigeminal nerve project to all of the above mentioned areas.The caudal subnucleus projects to the crus Ⅰ, the paramedian lobule, the dorsal paraflocculus, the lateral part of the lobule Ⅷ and the vermal cortex of the lobules Ⅵ～Ⅸ.The oral subnucleus gives its projections to the crus Ⅱ, the paramedian lobule, the lateral part of the lobule Ⅷ and the vermal cortex of the lobules Ⅶ～Ⅸ.The mesencephalic nucleus of the trigeminal nerve sends fibers to the crura Ⅰ and Ⅱ, the paramedian lobule, the lateral part of the lobule Ⅷ and the vermal cortex of lobules Ⅶ～Ⅸ.A few labeled neurons were found in the motor nucleus of the trigeminal nerve; while in the region ventro-lateral to the motor nucleus, in the root of the trigeminal nerve and in areas adjacent to it large amount of labeled cells were seen in all the cases studied.Unexpectedly, several labeled neurons were seen in a semilunar ganglion of the trigeminal nerve.
RESUMO
Eight rabbits were used in this study.The position of the phrenic nucleus in thespinal cord,the morphology of the phrenic motoneurones and position of the cellbodies of the sensory neurons of the phrenic nerve were determined by using themethod of HRP labelling through the centralcutting end of the left phrenic nerve atthe root of the neck.The results were as follows:1.The phrenic nucleus in the rabbit was located in C_3,C_4,and C_5 segments.Itis a longitudinal cell column lying between the ventromedial and the ventrolateralcolumns of the ventral horn of the spinal cord.2.Phrenic motoneurones differed in shape and size.Most of the cell bodies ofthe rabbit's phrenic motoneurones were round or oval in shape,ranging from 5 to45 ?m(mean 25 ?m)in diameter.3.The rabbit phrenic nerve arises from the ventral rami of the 3 rd,4 th and5 th cervical nerves,and the nucleus of this nerve does not extend beyond the 3 rd-5 th segments——the location of the nucleus corresponds with the segmental rootsfrom which the phrenic nerve arises.4.The cell bodies of the sensory neurones of the rabbit's phrenic nerve werelocated in the dorsal root ganglia of the third and fourth cervical nerves.Besides,50 rabbits were dissected,and the origin of their phrenic nerves werestudied.