大白鼠脚间核的传入性联系

本实验应用微量注射和离子透入法经三种不同入路,将HRP输入大鼠脚间核内,追踪脚间核的传入性联系。三种不同进针方向,共同出现标记神经元的核团除了缰内侧核、缰外侧核、中缝背核、中央上核、被盖背核、被盖背外侧核、导水管周围灰质外侧与腹外侧区和蓝斑以外,尚有Broca氏斜角带核和伏隔核。组内侧核和脚间核的联系存在着明显的局部定位关系,即双侧缰内侧核内侧投射至脚间核中部的腹侧和腹外侧;双侧缰内侧核外侧投射至脚间核中部的背侧;同侧缰内侧核投射至脚间核中部的外侧;双侧缰内侧核纤维并不投射至脚间核的吻端和尾端。本研究还发现其它核团对脚间核的投射也存在一定的局部定位关系,如缰外侧核、被盖背核腹内侧和被盖背外侧核均投射到脚间核的尾侧;伏隔核尾端也有投射纤维至脚间核。

AFFERENT CONNECTIONS OF THE INTERPEDUNCULAR NUCLEUS IN ALBINO RAT

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 follows:Following 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.