猫臂旁核向大脑皮质的投射——HRP逆轴突传递法研究

用HRP逆轴突传递法观察了24只猫臂旁核(PB)向大脑皮质的投射。结果表明:本实验所涉及到的所有皮质区均从PB接受数量不等的投射纤维。PB投射纤维的起源细胞主要分布在臂旁内侧核(PBm),少量在臂旁外侧核(PB1)和结合臂(CB)内;这些细胞主要出现在PB的吻侧2/3,以中等大的梭形细胞居多。根据各注射例PB内标记细胞数的多少可知:PB发出的纤维广泛投向皮质各脑回,重点投向前半皮质,其中前,后乙状回是投射中心,其余各脑回(包括未见报道的听区、梨状区、压上回、压旁回和海马)只接受PB的少量上行投射纤维。

PROJECTIONS OF THE PARABRACHIAL NUCLEUS TO THE CEREBRAL CORTEX IN THE CAT

The projections of the parabrachial nucleus (PB) to the cerebral cortex were studied with retrograde horseradish peroxidase (HRP) method in 24 cats. Injecting HRP into the differential cortical gyri or functional regions, we found retrogradely labeled cell bodies bilaterally with an ipsilateral predominence, in restricted region of the rostral two thirds of PB. Most of the labeled cells appeared in the medial parabrachial nucleus (PBm), a few in the lateral parabrachial nucleus (PB1) and conjunctional brachialis (CB). They were mainly fasiform in shape and medium in size. According to the calculations of the labeled cells in PB: the projecting fibers of the PB distributed widely to the whole cerebral cortex with a predominence in the anterior half, being densest in the anterior and posterior sigmoid gyri. Other cortical regions, including the auditory area, piriform area, suprasplenium gyrus, parasplenium gyrus and hippocampus that were not reported before, received less fibers of the PB.