AFFERENT CONNECTIONS OF THE PONTINE TEGMENTUM IN GUINEA PIGS HRP RETROGRADE TRACING METHOD / 解剖学报

ABSTRACT

The present study was undertaken to identify some afferent connections of the ventral and dorsal parts of pontine tegmentum in guinea pigs by using horseradish peroxidase retrograde microelectrophoretic technique.After introducing HRP into the ventral part of pontine tegmentum, numerous labeled cells were observed in the mesencephalic central gray and related reticular formation, which is equivalent to the MSR (Mesencephalic Stepping Region) ventral to the surface of the superior colliculus. Labeled cells could also be identified at the following sites nucleus cuneiformis ventral to the surface of inferior colliculus, nucleus tractus spinalis nervi trigemini, nucleus reticularis gigantocellularis, nucleus medialis vestibulares, nucleus lateralis vestibulares, nucleus loci coerulei and its ventral part, gray matter of the cervical enlargement of spinal cord.Following injection of HRP into the dorsal part of pontine tegmentum, substantial amount of labeled cells were observed in the nucleus reticularis pontis caudalis and nucleus reticularis gigantocellularis Labeled cells gould also be identi- fied in the nucleus medialis vestibulares, nucleus lateralis vestibulares and nucleus cuneatus. Only a few HRP cells appeared around the nucleus tuber in the midbrain and no labeled cells have been seen in the nucleus loci coerulei, as well as the gray matter of cervical spinal cord.