ABSTRACT
The afferent projections to the hippocampus were studied with HRP. Thirty three per cent solution of HRP was slowly injected into the dorsal or ventral hippocampus on its right side in 25 albino rats and HRP-labelled cells were found in the following nuclei:1. On the ipsilateral side: entorhinal cortex, medial septal nucleus, supramammillary nucleus, submammillothalamic nucleus, dorsal raphe nucleus, median raphe nucleus, locus coeruleus, diagonal band and nucleus of superior colliculus.2. On the contralateral side: areas CA_3 and CA_4 of hippocampus and locus coeruleus.
ABSTRACT
The segment length,the length of dorsal root attachment of each segment of the spinal cord of 10 adult men were measured.The cross sections from 4 specimens were stained with 1% osmic acid and the area of each section was measured with a com- pensating polar planimeter after being magnified 10 diameters.The segment volume was obtained by multiplying the segment length by the cross-sectlon area. The results shows that the length of spinal cords in Chinese are essentially the same as those from European and Japanese.They are approximately 44cm.in length. The length of each part of the cord in Chinese,European and Japanese were compared. The length of each part of the cord in Chinese and European are essentially alike,but the length of lumbar cord of Japanese appears to be slightly longer. The results show that the weight of the segment was closely related to the segment length. The coronal diameter of each segment is longer than the sagittal diameter,especial- ly it is true in the cervical enlargement.The longest coronal and sagittal diameters are found in the cervical enlargement,the next are in the lumbar enlargement,and the shortest are in the thoracic segment. The volume of the cervical segment and the lumbo-sacral segment is closely rela- ted to their cross-section area particularly to the area of their white matter. The volume of the gray matter of the cervical and the lumbo-sacral segments has a close relation to the gray matter area of the same segment,but that of the thoracic segment is related to its length. It is quite obvious that the volume of the white matter of both the cervical and lumbar enlargements reaches its highest value at segments higher than that of the gray matter,which may indicate that the increase in volume in the gray and white matter are dependent upon each other.
ABSTRACT
Ten adult rabbits (7 and ♀3; body weights 1.5～2 kg) were selected for thee present study. A solution of 2～10％ HRP (RZ=2.9) was injected into the subserosa of the caecum in seven rabbits and a solution of 5～10％ HRP into the deep peroneal nerve of Tsusanli (足三里) region in the other three. The uptake and retrograds transmission of HRP in the afferent fibres of both the somatic and visceral nerves were traced to the spinal ganglia. The range of segments where the neurons from which these two afferent fibres originate overlap each other. The results are a follows:1. Labelled sensory neurons from the region of the caecum where HRP was injected are observed in the spinal ganglia C_8～S_3 with a higher concentration in T_(11)～L_2.2. Labelled neurons from the region of Tsusanli are found in the spinal ganglia L_1～S_3 with a higher concentration in L_6～S_2.3. The ranges of distribution of labelled neurons from the two groups of afferent fibres overlap in the segments L_1～S_3.4. Most of the labelled cells are small and medium in size and the Iabelled cells are found more concentrated in the lumbosacral segments.