66 research outputs found
Cajal's prophetic functional considerations on respiratory reflexes: new questions about old answers
In the "Histology of the Nervous System" (Histologie, Spanish edition, 1899, 1904; French translation, 1909, 1911; all citations are from the American translation, 1995) Cajal did not only describe the origins and central pathways of cranial nerves but his detailed observations led him to numerous conclusions about the functional organization of brainstem reflexes. From studies of vagal and glossopharyngeal afferents he proposed a structural organization of the nucleus tractus solitarii (NTS). His view has been considerably changed by several authors on the basis of modem tracing studies. However, detailed histological examinations of functionally identified sensory fibers provided new understanding of a functional organization of the solitary nucleus that is very well in line with Cajal's original descriptions. The prophetic character of Cajal's concepts of structural-functional relations becomes even more evident by a reconsideration of his explanations of the reflexes underlying respiration, coughing and vomiting. Recent clectrophysiological studies of spontaneously rhythmically active in vitro preparations have provided us with new insights in respiratory control. However, it appears that quite a number of Cajal's key questions concerning respiratory reflexes are still not solved. Therefore, a reconsideration of old and partly forgotten concepts might indeed provide a novel understanding of the structural and functional organization of brainstem reflexes
Glial fibrillary acidic protein immunoreactive astrocytes in developing rat hippocampus
The developmental pattern of glial fibrillary acidic protein (GFAP)-immunoreactive astrocytes was investigated in the hippocampus (subfields CA1, CA3 and CA4) and in the dentate gyrus of male and female rats aged 11, 16, 30, 90 and 150 days by immunohistochemistry associated with image analysis. Analysis was centred on stratum radiatum, a hippocampal area rich in GFAP-immunoreactive astrocytes. The volume of different portions of hippocampus, the number and the size of astrocytes, the intensity of cell body GFAP immunostaining as well as the extension of astrocyte were assessed. A maturation pattern consisting in higher cellular expression of GFAP, an increase in overall cell size and expanding arborisation from the 11th to the 30th postnatal day, followed by stabilisation of these parameters until the 90th day of life, and a subsequent decrease in the oldest age group studied was found. A sex-related different temporal pattern of astrocytes maturation in size and GFAP content was observed in the CA1 subfield only. The increase of GFAP content during pre-weaning ages was less pronounced in females than in males as well as the decrease between the 90th and the 150th day of age. Moreover, the size of astrocytes was larger in females than in males at the 11th and 150th days of life. These findings Suggest that hippocampal astrocytes undergo rapid maturation in the 1st month of postnatal life, followed by a slow consolidation of this process until the 3rd month of life. At 5 months of age, there are still dynamic changes in the mature astrocytes, which become slender and thinner probably as a response to the increased volume of hippocampus noticeable at this age. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved
Chronic Supplementary dl-alpha Tocopheryl Acetate Stimulates Brain Accelerated Aging: S100B, RAGE and Microglia.
Stony Brook University Libraries.
SBU Graduate School in Psychology.
Lawrence Martin (Dean of Graduate School), Patricia M. Whitaker, Ph.D. - Dissertation Advisor
Professor, Department of Psychology, Hoi-Chung Leung, Ph.D. - Chairperson of Defense
Assistant Professor, Department of Psychology, Dr. Gregory Zelinsky, Ph.D.
Associate Professor, Department of Psychology, Efrain C. Azmitia, Ph.D.
Professor, Department of Biology,
New York University
Modern views on an ancient chemical: serotonin effects on cell proliferation, maturation, and apoptosis
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