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Tüfekci KK, Kaplan AA, Kaya A, Alrafiah A, Altun G, Aktaş A, Kaplan S. The potential protective effects of melatonin and omega-3 on the male rat optic nerve exposed to 900 MHz electromagnetic radiation during the prenatal period. Int J Neurosci 2023; 133:1424-1436. [PMID: 37712630 DOI: 10.1080/00207454.2023.2259078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 08/17/2023] [Accepted: 09/09/2023] [Indexed: 09/16/2023]
Abstract
BACKGROUND Due to children and adolescents' widespread use of electronic devices, researchers have focused on pre-and early postnatal electromagnetic field (EMF) exposure. However, little is known about the effects of EMF exposure on the optic nerve. The aim of study was to investigate the changes occurring in the optic nerve and the protective effects of melatonin (mel) and omega 3 (ω-3) in rats. METHODS Thirty-five pregnant rats were divided into seven groups, Cont, Sham, EMF, EMF + melatonin (EMF + Mel), EMF + ω3, Mel, and ω3. The EMF groups were exposed to 900 megahertz (MHz) EMF daily for two hours during pregnancy. After the experiment, the right optic nerve of each offspring rat was removed and fixed in glutaraldehyde. Thin and semi-thin sections were taken for electron microscopic and stereological analyses. Myelinated axon numbers, myelin sheath thicknesses, and axonal areas were estimated using stereological methods. RESULTS The groups had no significant differences regarding mean numbers of axons, mean axonal areas, or mean myelin sheath thicknesses (p > 0.05). Histological observations revealed impaired lamellae in the myelin sheath of most axons, and vacuolization was frequently observed between the myelin sheath and axon in the EMF-exposed group. The Mel and ω-3-treated EMF groups exhibited well-preserved myelinated nerve fibers and intact astrocytes and oligodendrocytes. CONCLUSIONS At the ultrastructural level, Mel and ω3 exhibits a neuroprotective effect on the optic nerve exposed to prenatal EMF. The protective effects of these antioxidants on oligodendrocytes, which play an essential role in myelin formation in the central nervous system, now require detailed investigation.
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Affiliation(s)
- Kıymet Kübra Tüfekci
- Department of Histology and Embryology, Faculty of Medicine, Kastamonu University, Kastamonu, Turkey
| | - Arife Ahsen Kaplan
- Department of Histology and Embryology, Faculty of Medicine, İstanbul Medipol University, İstanbul, Turkey
| | - Ayşenur Kaya
- Department of Histology and Embryology, Faculty of Medicine, Karamanoğlu Mehmetbey University, Karaman, Turkey
- Department of Histology and Embryology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Aziza Alrafiah
- Medical Laboratory Sciences Department, Faculty of Applied Medical Sciences, King Abdul Aziz University, Jeddah, Saudi Arabia
| | - Gamze Altun
- Department of Histology and Embryology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
| | - Abit Aktaş
- Department of Histology and Embryology, Faculty of Veterinary Medicine, İstanbul Cerrahpaşa University, İstanbul, Turkey
| | - Süleyman Kaplan
- Department of Histology and Embryology, Faculty of Medicine, Ondokuz Mayıs University, Samsun, Turkey
- Nelson Mandela African Institution of Science and Technology, Arusha, Tanzania
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Bolat D, Kürüm A, Canpolat S. Morphology and quantification of sheep pineal glands at pre-pubertal, pubertal and post-pubertal periods. Anat Histol Embryol 2018; 47:338-345. [PMID: 29774950 DOI: 10.1111/ahe.12359] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 04/17/2018] [Indexed: 12/01/2022]
Abstract
The pineal gland is a neuroendocrine organ associated with photoperiodic regulation in mammals. The aim of this study was to evaluate the pineal gland at the pre-pubertal, pubertal and post-pubertal periods by means of morphology and stereology. The study examined at total of 24 ovine pineal glands collected from healthy female Akkaraman breed. Thick sections (40 μm) were cut and treated with synaptophysin. Following each thick section, six consecutive sections at a thickness of 5 μm were cut. Each thin section was stained with one of the following dyes: Crossman's modified triple dye, glial fibrillary acidic protein (GFAP), melatonin marker, periodic acid-Schiff, Von Kossa and AgNOR. The pineal gland volume was measured using Cavalieri's method. The optical fractionator was used to estimate the total number of pinealocytes. The percentage of parenchyma and connective tissue and degree of vascularization were estimated by the area fraction fractionator method. The pineal gland volumes in the pre-pubertal, pubertal and post-pubertal groups were 7.53 ± 1.715 mm3 , 11.20 ± 1.336 mm3 and 17.75 ± 1.188 mm3 , respectively (p < .5). The number of pinealocytes in the pre-pubertal, pubertal and post-pubertal groups was 3,244,000 ± 228,076, 4,438,000 ± 243,610, 7,381,766 ± 406,223, respectively (p < .05). The glands of the post-pubertal group contained the highest amount of connective tissue (11.49 ± 2.103%; p < .5) and the largest GFAP staining area (p < .05). The melatonin staining density was the highest in the pubertal group. The density of lipofuscin staining was higher in the pubertal and post-pubertal groups.
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Affiliation(s)
- Durmuş Bolat
- Faculty of Veterinary Medicine, Department of Anatomy, Kırıkkale University, Yahsihan, Kırıkkale, Turkey
| | - Aytül Kürüm
- Faculty of Veterinary Medicine, Department of Histology and Embryology, Kırıkkale University, Yahsihan, Kırıkkale, Turkey
| | - Sıla Canpolat
- Faculty of Engineering, Multidisciplinary Laboratories, İzmir Economy University, Balcova, İzmir, Turkey
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Bolat D, Yıldız D, Bahar S, Yürüker S, Kaymaz F, Ilgın C, Bozkurt EÜ, Karahan S, Sabancı SS. A comparative study of oculomotor, trochlear and abducens nerves in Arabian foals. Biotech Histochem 2017; 92:149-156. [PMID: 28296553 DOI: 10.1080/10520295.2017.1288926] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
We investigated the microscopic structure of transverse sections of the oculomotor, trochlear and abducens nerves of Arabian foals using stereological methods. Bilateral nerve pairs from 2-month-old female Arabian foals were analyzed. The tissues were embedded in plastic blocks, then 1 µm thick sections were cut and stained with osmium tetroxide and methylene blue-azure II. Stereology was performed using light microscopy. Morphometry showed that the right and left pairs of nerves were similar. The transverse sectional areas of the oculomotor, trochlear and abducens nerves were 1.93 ± 0.19 mm2, 0.32 ± 0.06 mm2 and 0.70 ± 0.08 mm2, respectively. The oculomotor nerve exhibited a significantly greater number of myelinated axons (16755 ± 1279) and trochlear (2656 ± 494) and the abducens nerves (4468 ± 447). The ratio of the axon diameter to myelinated nerve fiber diameter was 0.58, 0.55 and 0.55 for the oculomotor, trochlear and abducens nerves, respectively. Of the three nerves studied, the abducens nerve exhibited the greatest nerve fiber area, myelin area, nerve and axon diameters, and myelin thickness. The ratio of small myelinated nerve fibers was greatest in the oculomotor nerve.
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Affiliation(s)
- D Bolat
- a Faculty of Veterinary Medicine, Department of Anatomy , Kırıkkale University , Kırıkkale
| | - D Yıldız
- a Faculty of Veterinary Medicine, Department of Anatomy , Kırıkkale University , Kırıkkale
| | - S Bahar
- b Faculty of Veterinary Medicine, Department of Anatomy , Selçuk University , Konya
| | - S Yürüker
- c Faculty of Medicine, Department of Histology and Embryology , Hacettepe University , Ankara
| | - F Kaymaz
- c Faculty of Medicine, Department of Histology and Embryology , Hacettepe University , Ankara
| | - C Ilgın
- c Faculty of Medicine, Department of Histology and Embryology , Hacettepe University , Ankara
| | - E Ü Bozkurt
- a Faculty of Veterinary Medicine, Department of Anatomy , Kırıkkale University , Kırıkkale
| | - S Karahan
- d Faculty of Veterinary Medicine, Department of Histology and Embryology , Kırıkkale University , Kırıkkale , Turkey
| | - S S Sabancı
- a Faculty of Veterinary Medicine, Department of Anatomy , Kırıkkale University , Kırıkkale
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Junatas KL, Tonar Z, Kubíková T, Liška V, Pálek R, Mik P, Králíčková M, Witter K. Stereological analysis of size and density of hepatocytes in the porcine liver. J Anat 2016; 230:575-588. [PMID: 28032348 DOI: 10.1111/joa.12585] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/22/2016] [Indexed: 02/06/2023] Open
Abstract
The porcine liver is frequently used as a large animal model for verification of surgical techniques, as well as experimental therapies. Often, a histological evaluation is required that include measurements of the size, nuclearity or density of hepatocytes. Our aims were to assess the mean number-weighted volume of hepatocytes, the numerical density of hepatocytes, and the fraction of binuclear hepatocytes (BnHEP) in the porcine liver, and compare the distribution of these parameters among hepatic lobes and macroscopic regions of interest (ROIs) with different positions related to the liver vasculature. Using disector and nucleator as design-based stereological methods, the morphometry of hepatocytes was quantified in seven healthy piglets. The samples were obtained from all six hepatic lobes and three ROIs (peripheral, paracaval and paraportal) within each lobe. Histological sections (thickness 16 μm) of formalin-fixed paraffin-embedded material were stained with the periodic acid-Schiff reaction to indicate the cell outlines and were assessed in a series of 3-μm-thick optical sections. The mean number-weighted volume of mononuclear hepatocytes (MnHEP) in all samples was 3670 ± 805 μm3 (mean ± SD). The mean number-weighted volume of BnHEP was 7050 ± 2550 μm3 . The fraction of BnHEP was 4 ± 2%. The numerical density of all hepatocytes was 146 997 ± 15 738 cells mm-3 of liver parenchyma. The porcine hepatic lobes contained hepatocytes of a comparable size, nuclearity and density. No significant differences were identified between the lobes. The peripheral ROIs of the hepatic lobes contained the largest MnHEP with the smallest numerical density. The distribution of a larger MnHEP was correlated with a larger volume of BnHEP and a smaller numerical density of all hepatocytes. Practical recommendations for designing studies that involve stereological evaluations of the size, nuclearity and density of hepatocytes in porcine liver are provided.
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Affiliation(s)
- Khan L Junatas
- Department for Pathobiology, Institute of Anatomy, Histology and Embryology, University of Veterinary Medicine Vienna, Vienna, Austria.,College of Veterinary Medicine, University of Southern Mindanao, Cotabato, Philippines
| | - Zbyněk Tonar
- Department of Histology and Embryology and Biomedical Center, Faculty of Medicine in Pilsen, Charles University in Prague, Pilsen, Czech Republic
| | - Tereza Kubíková
- NTIS, European Centre of Excellence, Faculty of Applied Sciences, University of West Bohemia, Pilsen, Czech Republic
| | - Václav Liška
- Department of Surgery and Biomedical Center, Faculty of Medicine in Pilsen, Charles University in Prague, Pilsen, Czech Republic
| | - Richard Pálek
- Department of Surgery and Biomedical Center, Faculty of Medicine in Pilsen, Charles University in Prague, Pilsen, Czech Republic
| | - Patrik Mik
- Department of Anatomy, Faculty of Medicine in Pilsen, Charles University in Prague, Pilsen, Czech Republic
| | - Milena Králíčková
- Department of Histology and Embryology and Biomedical Center, Faculty of Medicine in Pilsen, Charles University in Prague, Pilsen, Czech Republic
| | - Kirsti Witter
- Department for Pathobiology, Institute of Anatomy, Histology and Embryology, University of Veterinary Medicine Vienna, Vienna, Austria
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Barger N, Sheley MF, Schumann CM. Stereological study of pyramidal neurons in the human superior temporal gyrus from childhood to adulthood. J Comp Neurol 2015; 523:1054-72. [PMID: 25556320 DOI: 10.1002/cne.23707] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2014] [Revised: 10/25/2014] [Accepted: 10/30/2014] [Indexed: 01/11/2023]
Abstract
The association cortex of the superior temporal gyrus (STG) is implicated in complex social and linguistic functions. Thus, reliable methods for quantifying cellular variation in this region could greatly benefit researchers interested in addressing the cellular correlates of typical and atypical function associated with these critical cognitive abilities. To facilitate this task, we first present a general set of cytoarchitectonic criteria targeted specifically toward stereological analyses of thick, Nissl-stained sections for the homotypical cortex of the STG, referred to here as BA22/TA. Second, we use the optical fractionator to estimate pyramidal neuron number and the nucleator for pyramidal somal and nuclear volume. We also investigated the influence of age and sex on these parameters, as well as set a typically developing baseline for future comparisons. In 11 typically developing cases aged 4-48 years, the most distinguishing features of BA22/TA were the presence of distinct granular layers, a prominent, jagged layer IIIc, and a distinctly staining VIa. The average number of neurons was 91 ± 15 million, the volume of pyramidal soma 1,512 µm(3) , and the nuclear volume 348 µm(3) . We found no correlation with age and neuron number. In contrast, pyramidal somal and nuclear volume were both negatively correlated and linearly associated with age in regression analyses. We found no significant sex differences. Overall, the data support the idea that postnatal neuron numbers are relatively stable through development but also suggest that neuronal volume may be subject to important developmental variation. Both measures are critical variables in the study of developmental neuropathology.
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Affiliation(s)
- Nicole Barger
- Department of Psychiatry and Behavioral Sciences, MIND Institute, University of California, Davis, Sacramento, California, 95817
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Wegiel J, Flory M, Kuchna I, Nowicki K, Ma SY, Imaki H, Wegiel J, Cohen IL, London E, Brown WT, Wisniewski T. Brain-region-specific alterations of the trajectories of neuronal volume growth throughout the lifespan in autism. Acta Neuropathol Commun 2014; 2:28. [PMID: 24612906 PMCID: PMC4007529 DOI: 10.1186/2051-5960-2-28] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2014] [Accepted: 02/21/2014] [Indexed: 01/17/2023] Open
Abstract
Several morphometric studies have revealed smaller than normal neurons in the neocortex of autistic subjects. To test the hypothesis that abnormal neuronal growth is a marker of an autism-associated global encephalopathy, neuronal volumes were estimated in 16 brain regions, including various subcortical structures, Ammon's horn, archicortex, cerebellum, and brainstem in 14 brains from individuals with autism 4 to 60 years of age and 14 age-matched control brains. This stereological study showed a significantly smaller volume of neuronal soma in 14 of 16 regions in the 4- to 8-year-old autistic brains than in the controls. Arbitrary classification revealed a very severe neuronal volume deficit in 14.3% of significantly altered structures, severe in 50%, moderate in 21.4%, and mild in 14.3% structures. This pattern suggests desynchronized neuronal growth in the interacting neuronal networks involved in the autistic phenotype. The comparative study of the autistic and control subject brains revealed that the number of structures with a significant volume deficit decreased from 14 in the 4- to 8-year-old autistic subjects to 4 in the 36- to 60-year-old. Neuronal volumes in 75% of the structures examined in the older adults with autism are comparable to neuronal volume in age-matched controls. This pattern suggests defects of neuronal growth in early childhood and delayed up-regulation of neuronal growth during adolescence and adulthood reducing neuron soma volume deficit in majority of examined regions. However, significant correction of neuron size but limited clinical improvements suggests that delayed correction does not restore functional deficits.
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Affiliation(s)
- Jerzy Wegiel
- Department of Developmental Neurobiology, NYS Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314, USA
| | - Michael Flory
- Department of Infant Development, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Izabela Kuchna
- Department of Developmental Neurobiology, NYS Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314, USA
| | - Krzysztof Nowicki
- Department of Developmental Neurobiology, NYS Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314, USA
| | - Shuang Yong Ma
- Department of Developmental Neurobiology, NYS Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314, USA
| | - Humi Imaki
- Department of Developmental Neurobiology, NYS Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314, USA
| | - Jarek Wegiel
- Department of Developmental Neurobiology, NYS Institute for Basic Research in Developmental Disabilities, 1050 Forest Hill Road, Staten Island, NY 10314, USA
| | - Ira L Cohen
- Department of Psychology, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Eric London
- Department of Psychology, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - W Ted Brown
- Department of Human Genetics, NYS Institute for Basic Research in Developmental Disabilities, Staten Island, NY, USA
| | - Thomas Wisniewski
- Department of Psychiatry, Neurology and Pathology, New York University School of Medicine, New York, NY, USA
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Bogdan S, Schultz J, Grosshans J. Formin' cellular structures: Physiological roles of Diaphanous (Dia) in actin dynamics. Commun Integr Biol 2014; 6:e27634. [PMID: 24719676 PMCID: PMC3977921 DOI: 10.4161/cib.27634] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2013] [Revised: 12/21/2013] [Accepted: 12/23/2013] [Indexed: 01/06/2023] Open
Abstract
Members of the Diaphanous (Dia) protein family are key regulators of fundamental actin driven cellular processes, which are conserved from yeast to humans. Researchers have uncovered diverse physiological roles in cell morphology, cell motility, cell polarity, and cell division, which are involved in shaping cells into tissues and organs. The identification of numerous binding partners led to substantial progress in our understanding of the differential functions of Dia proteins. Genetic approaches and new microscopy techniques allow important new insights into their localization, activity, and molecular principles of regulation.
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Affiliation(s)
- Sven Bogdan
- Institut für Neurobiologie; Universität Münster; Münster, Germany
| | - Jörg Schultz
- Bioinformatik, Biozentrum; Universität Würzburg; Würzburg, Germany
| | - Jörg Grosshans
- Institut für Biochemie; Universitätsmedizin; Universität Göttingen; Göttingen, Germany
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Lifshitz J, Lisembee AM. Neurodegeneration in the somatosensory cortex after experimental diffuse brain injury. Brain Struct Funct 2012; 217:49-61. [PMID: 21597967 PMCID: PMC3536493 DOI: 10.1007/s00429-011-0323-z] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Accepted: 04/28/2011] [Indexed: 10/18/2022]
Abstract
Disruption and consequent reorganization of central nervous system circuits following traumatic brain injury may manifest as functional deficits and behavioral morbidities. We previously reported axotomy and neuronal atrophy in the ventral basal (VB) complex of the thalamus, without gross degeneration after experimental diffuse brain injury in adult rats. Pathology in VB coincided with the development of late-onset aberrant behavioral responses to whisker stimulation, which lead to the current hypothesis that neurodegeneration after experimental diffuse brain injury includes the primary somatosensory barrel cortex (S1BF), which receives projection of VB neurons and mediates whisker somatosensation. Over 28 days after midline fluid percussion brain injury, argyrophilic reaction product within superficial layers and layer IV barrels at 1 day progresses into the cortex to subcortical white matter by 7 days, and selective inter-barrel septa and subcortical white matter labeling at 28 days. Cellular consequences were determined by stereological estimates of neuronal nuclear volumes and number. In all cortical layers, neuronal nuclear volumes significantly atrophied by 42-49% at 7 days compared to sham, which marginally attenuated by 28 days. Concomitantly, the number of healthy neurons was reduced by 34-45% at 7 days compared to sham, returning to control levels by 28 days. Progressive neurodegeneration, including argyrophilic reaction product and neuronal nuclear atrophy, indicates injury-induced damage and reorganization of the reciprocal thalamocortical projections that mediate whisker somatosensation. The rodent whisker barrel circuit may serve as a discrete model to evaluate the causes and consequences of circuit reorganization after diffuse brain injury.
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Affiliation(s)
- Jonathan Lifshitz
- Spinal Cord and Brain Injury Research Center, University of Kentucky Chandler Medical Center, Office B463, Biomedical and Biological Sciences Research Building, 741 S. Limestone St, Lexington, KY 40536-0509, USA.
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HENRIQUE RUIMF, ROCHA EDUARDO, REIS ALCINDA, MARCOS RICARDO, OLIVEIRA MARIAH, SILVA MARIAW, MONTEIRO ROGÉRIOAF. Age-related changes in rat cerebellar basket cells: a quantitative study using unbiased stereological methods. J Anat 2001; 198:727-36. [PMID: 11465864 PMCID: PMC1468261 DOI: 10.1046/j.1469-7580.2001.19860727.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Cortical cerebellar basket cells are stable postmitotic cells; hence, they are liable to endure age-related changes. Since the cerebellum is a vital organ for the postural control, equilibrium and motor coordination, we aimed to determine the quantitative morphological changes in those interneurons with the ageing process, using unbiased techniques. Material from the cerebellar cortex (Crus I and Crus II) was collected from female rats aged 2, 6, 9, 12, 15, 18, 21 and 24 mo (5 animals per each age group), fixed by intracardiac perfusion, and processed for transmission electron microscopy, using conventional techniques. Serial semithin sections were obtained (5 blocks from each rat), enabling the determination of the number-weighted mean nuclear volume (by the nucleator method). On ultrathin sections, 25 cell profiles from each animal were photographed. The volume density of the nucleus, ground substance, mitochondria, Golgi apparatus (Golgi) and dense bodies (DB), and the mean surface density of the rough endoplasmic reticulum (RER) were determined, by point counting, using a morphometric grid. The mean total volumes of the soma and organelles and the mean total surface area of the RER [SN (RER)] were then calculated. The results were analysed with 1-way ANOVA; posthoc pairwise comparisons of group means were performed using the Newman-Keuls test. The relation between age and each of the parameters was studied by regression analysis. Significant age-related changes were observed for the mean volumes of the soma, ground substance, Golgi, DB, and SN (RER). Positive linear trends were found for the mean volumes of the ground substance, Golgi, and DB; a negative linear trend was found for the SN (RER). These results indicate that rat cerebellar basket cells endure important age-related changes. The significant decrease in the SN (RER) may be responsible for a reduction in the rate of protein synthesis. Additionally, it may be implicated in a cascade of events leading to cell damage due to the excitotoxic activity of glutamate, which could interfere in the functioning of the complex cerebellar neuronal network.
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Affiliation(s)
- RUI M. F.
HENRIQUE
- Laboratory of Histology and Embryology, Institute of Biomedical Sciences, University of Oporto, Portugal
- Correspondence to Prof. Rogério A. F. Monteiro, Laboratory of Histology and Embryology, Institute of Biomedical Sciences, Largo Professor Abel Salazar no. 2, 4099-003 Porto, Portugal. Tel.: +351 22 2062254; fax: +351 22 2062232; e-mail:
| | - EDUARDO ROCHA
- Laboratory of Histology and Embryology, Institute of Biomedical Sciences, University of Oporto, Portugal
| | - ALCINDA REIS
- Laboratory of Histology and Embryology, Institute of Biomedical Sciences, University of Oporto, Portugal
| | - RICARDO MARCOS
- Laboratory of Histology and Embryology, Institute of Biomedical Sciences, University of Oporto, Portugal
| | - MARIA H.
OLIVEIRA
- Laboratory of Histology and Embryology, Institute of Biomedical Sciences, University of Oporto, Portugal
| | - MARIA W.
SILVA
- Laboratory of Histology and Embryology, Institute of Biomedical Sciences, University of Oporto, Portugal
| | - ROGÉRIO A. F.
MONTEIRO
- Laboratory of Histology and Embryology, Institute of Biomedical Sciences, University of Oporto, Portugal
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