摘要:

AbstractHyperosmotic solutions of 3 M urea, either infused into one internal carotid artery or applied topically to the pia mater of rabbits, results in the opening of endothelial tight junctions through which horseradish peroxidase passes from blood to extracellular fluid of the brain. The evidence for this opening of the blood‐brain barrier to protein is the entry of peroxidase into the extracellular pools between successive tight junctions. In animals not receiving 3 M urea, the interjunctional pools are inaccessible to proteins. Having passed through the endothelial junctions, the peroxidase spreads along the extracellular channels of the perivascular neuropil for approximately 100 μ in 90 seconds. Most of the affected vessels are capillaries, though larger vessels are rendered leaky as well. Calyciform cisterns, that lie beneath shallow notches in the endothelium of untreated rabbits, appear to be enlarged after the administration of 3 m urea. It is undetermined whether these few endothelial cisterns and vesicles are involved in carrying protein from blood to the cerebral extracellular flu

ISSN:0092-7317    

DOI:10.1002/cne.901520402

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractThree types of neuron with differences in Nissl pattern were found in the red nucleus of the rhesus monkey. Neurons with coarse Nissl bodies occurred only in the caudal third of the red nucleus except for a small number which extended rostrally a short distance along the dorsolateral margin. Neurons with fine Nissl bodies occupied the rostral two‐thirds of the nucleus. Neurons with slight cytoplasmic basophilia (achromatic) were smaller than the other types and distributed throughout the red nucleus. Perikaryal areas of the coarse and fine neurons, measured with a computer, had widely overlapping distributions.Electrolytic lesions were made unilaterally in the red nucleus of nine monkeys. Ascending axonal degeneration was studied in sections stained by the Fink‐Heimer method. Two separate descending tracts were followed. The rubrobulbo‐spinal tract took origin from coarse neurons, crossed completely in the ventral tegmental decussation, and terminated as follows: in parts of the superior sensory trigeminal, motor facial and lateral reticular nuclei; in the gracile and cuneate nuclei; in the nucleus medullae oblongata, subnucleus dorsalis; in Rexed's laminae V, VI, VII at all levels of the spinal cord. In contrast, the rubroreticulo‐olivary tract took origin from fine neurons, remained uncrossed, and terminated in some reticular nuclei (pedunculopontine, pontis oralis and caudalis, gigantocellularis) and in parts of the inferior olivary complex. Degeneration was profuse in the dorsal lamina of the main olive, abundant in the ventral lamina, particularly in its lateral side, sparse and inconstant in the medial accessory olive, and invariably absent in the dorsal accessory olive. Thus, nuclei which receive descending projections from the red nucleus may be grouped into those with connections to lower motor neurons, cerebellum, or t

ISSN:0092-7317    

DOI:10.1002/cne.901520403

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractThe topography of the various groups of catecholamine‐ and serotonin‐containing cell bodies in the squirrel monkey (Saimiri sciureus), as described in the preceding three papers of this series, is presented in an atlas of Nissl and myelin stained frontal sections. The major findings of this study are reviewed and discussed. These include: (1) evidence of fundamental similarities in the topographic distribution of the cell groups between the primate and the rat and of significant differences between the primate and the cat; (2) identification as the catecholaminergic cells of the locus caeruleus of a cellular group incorrectly identified in the literature as nucleus tracti mesencephalici nervi trigemini; (3) consolidation of several catecholamine‐containing cell groups as belonging respectively to the locus caeruleus (C4, C6, C7) and the substantia nigra (C8 and C9); (4) predominant distribution of the serotoninergic cell groups in the midline raphe region (with lateral extensions in some cases) and location within well defined nuclei, such as the nucleus raphe obscurus, nucleus raphe pallidus, nucleus raphe magnus, nucleus raphe pontis, nucleus raphe dorsalis and nucleus centralis sup

ISSN:0092-7317    

DOI:10.1002/cne.901520404

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractThe organization of the facial nucleus was studied in the opossum by localizing neurons which stin poorly for acetylcholinesterase activity following transection of identified facial rami. The caudal auricular representation is limited to the ventromedial extreme of the nucleus, whereas the neurons contributing to the cervical ramus are situated dorsally and medially. The zygomatic representation extends throughout the intermediate portion of the nucleus, apparently overlapping with that of the palpebral and rostral auricular muscles which is limited to the ventral extreme of the intermediate zone. The buccolabial area is particularly large in the opossum and encompasses most of the lateral facial enlargement.Midbrain‐facial projections were identified from the superior colliculus, the midbrain tegmentum (particularly caudal ventromedial areas) and the red nucleus. The location of terminal degeneration in the facial nucleus following lesions within each of these areas was plotted and interpreted in light of facial organization. Of particular note is the fact that the fibers of rubral origin distribute preferentially to the zygomatic and, to some extent, buccolabial areas, whereas the ventromedial tegmental system distributes most strongly to the areas of caudal auricular, cervical, palpebral and rostral auricualar representation. The medial and intermediate regions of the facial nucleus receive a denser midbrain projection than does the lateral (buccolabial) area. In contrast, evidence was obtained for an extensive facial projection from the parvocellular reticular formation and the caudal spinal trigeminal nucleus which strongly favors the buccolabial enlargement. The possibility exists that the medial pontine and medullary reticular formation as well as portions of the dorsal column nuclei also have a facial projection. Spino‐facial fibers arise rostral to the cervical enlargement and show a predilection for the medial facial enlargement (cervical and caudal auricular areas). Although some systems distribute preferentially to specific areas of the facial nucleus, overlap is present suggesting considerable integrat

ISSN:0092-7317    

DOI:10.1002/cne.901520405

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

摘要:

AbstractAn atlas of the cerebral ganglion ofM. hirudinaceushas been constructed and the cells identified by number. There is a total of eighty‐six cells, three of which are binucleate. These cells (30, 80 and 90) are located in the frontal plane. Most cells give rise to bilateral processes and are organized in such a way that there is an outer coat of somata or cell bodies and a center core or neuropile. Some cell processes are 8 μ in diameter and most exit the ganglion via nerves of the opposite side. The cytoarchitecture of these cells indicates most have perinuclear rings and a well defined nucleolus. However, considerable variation occurs in number and distribution of cytoplasmic granul

ISSN:0092-7317    

DOI:10.1002/cne.901520406

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY

ISSN:0092-7317    

DOI:10.1002/cne.901520401

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1973

数据来源: WILEY