AFFERENT CONNECTIONS OF THE INTERPEDUNCULAR NUCLEUS IN ALBINO RAT / 解剖学报

ABSTRACT

The afferent connections of the interpeduncular nucleus (IPN) were studied with retrograde transport method of using horseradish peroxidase (HRP).A microinjected syringe needle or microelectrophoretic pipette was inserted into the brain in the vertical, inclined through cerebellum or inclined through cerebral cortex medially.The results were as followsFollowing HRP injection into the IPN, labeled neurons were found in medial habenular nuclei, lateral habenular nuclei, dorsal raphe nucleus, superior central nucleus, dorsal tegmental nucleus of Gudden, dorsolateral tegmental nucleus, ventro-lateral and lateral portions of periaqueductal grey matter, and locus coeruleus. In addition, labeled cells were also observed within caudal portion of accumbens nucleus and nucleus tractus diagonalis (Broca).Following HRP injection into the lateral, ventral (or ventrolateral) and dorsal portions of the IPN, labeled cells were found in ipslateral medial habenular nucleus,medial regions of the bilateral medial habenular nuclei, and lateral regions of the bilateral medial habenular nuclei, respectively.After injection into the rostral or caudal pole of the IPN, no labeled cells were observed in bilateral medial habenular nuclei.Following injection of HRP into the caudal pole of the IPN, labeled neurons were observed within both sides of lateral habehular nucleus, dorsolateral tegmental nucleus and ventromedial portion of dorsal tegmental nucleus.No labeled neurons were observed in the ventral (deep) tegmental nucleus,premamillary nucleus, supramamillary nucleus and parabigeminal nucleus except in the cases in which the HRP injection site extended beyond the IPN.