ISSN:0092-7317    

DOI:10.1002/cne.901680102

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

年代:1976

数据来源: WILEY

摘要:

AbstractThe observations here on Golgi material are based on the study of fortunate impregnations in one horizontally sectioned and one frontally sectioned series found in the collection of Golgi preparations of the adult monkey brains (Macaca mulatta) available in this laboratory.The soma of the large supraoptic neurons have jagged protrusions and irregular crevices which give their surfaces a craggy appearance. Also they have a few somatic spines. Their dendrites, which usually arise from two or three dendritic trunks, emerging from the cell body, are moderately branched and have occasional dendritic spines. The axon emerges from a conical elevation either on the soma or a dendrite and is directed towards the supraopticohypophysical tract.In the present material there are a few neurons of the supraoptic nucleus impregnated that are definitely smaller than the larger neurons. They have short beaded axons, ending in the supraoptic nucleus a short distance from their point of origin.In the horizontal sections the supraopticohypophysial tract fibers can be seen passing over the posterior aspect of the optic tract. In the frontal sections, this fan‐shaped tract, wide above and constricted below, can be followed into the median eminence. Some of these axons in their intrahypothalamic course have short beaded collaterals.Electron micrographs reveal: (1) endings with spherical synaptic vesicles and endings with flattened synaptic vesicles synapsing on neurosecretory axons in the supraoptic nucleus; (2) a few myelinated fibers containing neurosecretory granules in the intrahypothalamic portion of the supraopticohypophysial tract.As can be seen in both Golgi and electron microscopic preparations the presence of fibrous astrocytes in the supraoptic nucleus and their abundance in the hypothalamic portion of the supraopticohypophysial tract is characteristic of this neurosecretory system. In the nucleus and in the tract processes of the fibrous astrocytes are intimately associated with neurosecretory fiber

ISSN:0092-7317    

DOI:10.1002/cne.901680103

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

年代:1976

数据来源: WILEY

摘要:

AbstractThe neurons of the nucleus centrum medianum and the neurons of the nucleus parafascicularis were studied in Golgi preparations of the adult monkey(Macaca mulatta)The cell bodies of the principal neurons in the nucleus centrum medianum have a few somatic spines and vary in shape: some are cubical with protruding angles; some are egg‐shaped;some are elongated and sausage‐shaped. Four to six slightly branched dendrites of unequal thickness radiate from the cell body. Some dendrites extend for nearly 500 microns; all have dendritic spines.In the nucleus parafascicularis there are two varieties of principal neurons:(1) neurons with somatic spines and(2) neurons without somatic spines. The neurons with somatic spines are most numerous. They have polygonal‐shaped cell bodies, prominent somatic spines and processes, larger than spines but considerably smaller than dendrites. These processes bear spines and are designated here “microdendrites.” Spines and occasionally a “microdendrite” are found on the axon‐hillocks. Five to six dendrites of unequal thickness emerge from the cell bodies. Some extend for more than 500 microns; all have prominent dendritic spines.The neurons without somatic spines are relatively few. Usually three exceptionally long, slightly branched dendrites, one apical and two basal, emerge from their elongated, slim cell bodies. Some dendrites extend for more than 800 microns; all have a few scattered spines.The Golgi type II neurons found in both of these intralaminar nuclei have small cell bodies and a few, relatively long, undulating dendrites, which bear bulbous dendritic appendages and beaded axon‐like processes. Distally on these dendrites, where the appendages and processes are more numerous, the dendritic appendages and axon‐like processes form complex entanglements. Beaded axons are found on some but not all of the cell bodies. Morphologically these neurons resemble the local interneurons that have been described in vari

ISSN:0092-7317    

DOI:10.1002/cne.901680104

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

年代:1976

数据来源: WILEY

摘要:

AbstractIn Golgi preparations of the adult monkey(Macaca mulatta) local interneurons and two varieties of principal neurons, radiating and elongated fusiform, are found in the subthalamic nucleus. The cell bodies of the radiating neurons have a few delicate, somatic spines some of which are occasionally bilobed and trilobed. Five to eight dendritic trunks give rise to branching, tapering dendrites, which may extend for over 400 microns. These dendrites are much thinner than the dendrites in the globus pallidus and the substantia nigra. Some neurons have many and some neurons have few dendritic spines. When numerous the dendritic spines are concentrated on the dendritic trunks and proximal dendrites. The relatively few elongated fusiform neurons are found not only in the capsule but also in the center of the nucleus. Most dendrites emerge from the opposite poles of their smooth surfaced cell bodies. They have a few dendritic spines. Some of these dendrites extend for more than 750 microns.In 1‐micron thick plastic sections lipofuscin granules are present in some but not all principal neuron cell bodies of the pig‐tail monkey(Macaca mulatta); but these granules are present in all principal neuron cell bodies of the pig‐tail monkey(Macaca nemestrina) and of the squirrel monkey (Saimiri sciureus).The local interneurons have small cell bodies and a few relatively long undulating dendrites. The dendrites have bulbous dendritic appendages of varying complexity and beaded axon‐ like processes. The dendritic appendages and axon‐like processes are more numerous distally and on the distal ends of the dendrites they form complex entanglements. Axons coming from the cell body have not been observed. The cell bodies of the local interneurons are identified in cresyl violet stained sections of the monkey (Macaca mulatta), in 1‐micron thick plastic sections and electron micrographs of the squirrel monkey(Saimiri sciureus). They have relatively large nuclei surrounded by a thin rim of cytoplasm rich in po

ISSN:0092-7317    

DOI:10.1002/cne.901680105

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

年代:1976

数据来源: WILEY

摘要:

AbstractIn horizontally and sagittally sectioned Golgi preparations of the adult monkey spinal cord the afferent fibers in the substantia gelatinosa(laminae II and III of Rexed, '52) were studied with the hope of finding clues that would make it possible to correlate them with the afferent fibers that Ramón y Cajal ('09) traced from the white matter into the substantia gelatinosa in Golgi preparations of the newborn cat.Throughout the substantia gelatinosa there are fibers with fine terminal branches, bearing small “bouton en passant” endings. These fine terminal branches and the collaterals of the axons of the neurons in the substantia gelatinosa are similar; hence, the fine terminal branches are interpreted as the terminals of the proprius bundles generated by the axons of the neurons in the substantia gelatinosa. Also, there are fibers in lamina II that can be followed for relatively long distances(900 microns) before they are cut off in section. They have collaterals bearing large irregular endings, which usually consist of several or more elongated swellings connected by constricted regions. Some of these endings have holes within them and their surfaces have prominent indentations.The fibers with fine terminal branches and the fibers with large irregular endings are interpreted here as the two varieties of fine or superficial collaterals of the substance of Rolando described by Ramón y Cajal('09).The most elaborate afferent formations in the present material are found in horizontal sections. They are designated “confined ansiform axonal complexes” and are confined to elongated, oblong blocks of substantia gelatinosa that approximate each other in length, width and depth. Their branches, running rostrally and caudally, loop back and forth, interweave in an intricate pattern and bear large synaptic endings. because these formations are elaborate and because their parent fibers and initial branches are thicker in lamina III than they are in lamina II, these complexes are interpreted here as the large or deep collaterals of the substance of Rolando described by Ramón y Cajal('09). Considering their shapes, sizes and surface contours, it is probable that the large endings on the ansiform axonal complexes and the large irregular endings on the long fibers in lamina II are the central terminals in the glomeruli of the substantia gelatinosa that have been revealed by electron microscopy.Finally, there are fine collaterals from fibers in Lissauer's fasciculus which distribute exclusively to the marginal zone (lamina I) of the dorsal horn. Their endings are ovoid or bulbous and are almost uniformly approximately 2 microns in diameter. Undoubtedly, these collaterals are the marginal collaterals Ramón y Cajal ('09) demonstrated in Ehrlich's methylene blue preparations of the 8

ISSN:0092-7317    

DOI:10.1002/cne.901680106

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

年代:1976

数据来源: WILEY

摘要:

AbstractIn Golgi preparations of the adult monkey(Macaca mulatta) two types of neurons are distinguished in the pontine gray: (1) larger neurons which impregnate most frequently and(2) smaller neurons which impregnate rarely. The former are judged to be projection neurons with myelinated axons because only the initial segments of their axons impregnate, while the latter are judged to be intrinsic neurons since they appear to participate only in the local circuitry of the pontine gray.The projection neurons show a variety of sizes and shapes and are the equivalent of the large, medium and small neurons that Ramón y Cajal ('09) illustrated in the pons of the 5‐day‐old infant. Their cell bodies are rounded, polygonal, triangular, egg‐, pear‐, and spindle‐shaped. Some have somatic spines. Usually four to seven dendrites issue from the cell body and as they branch they attenuate. The dendrites have knobby, nodular protuberances which give them a gnarled appearance. Also the dendrites have a few scattered spines. In most instances the dendrites have a wavy recurring pattern. Neurons pressed against the corticospinal, corticopontine fiber bundles frequently have elongated cell bodies and the dendrites sprouting from them form tight, brush‐like arrays.The intrinsic neurons have small ellipsoid or pear‐shaped cell bodies and two to three long dendrites, which do not taper. In some impregnations short axons issuing from the cell body were found and in other impregnations several widely separated, short axon‐like processes were found on dendrites. A striking feature of the intrinsic neurons is the presence of stalked dendritic appendages bearing one or more bulbous bodies, 1 to 3 microns in diameter. The intrinsic neurons in no way resemble the hairy or mossy cells with short axis cylinders that Ramón y Cajal ('09) described in the pons of the 5‐day‐old infant. The latter were not found in

ISSN:0092-7317    

DOI:10.1002/cne.901680107

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

年代:1976

数据来源: WILEY

ISSN:0092-7317    

DOI:10.1002/cne.901680101

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

年代:1976

数据来源: WILEY