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1.
Food Sci Technol Int ; 16(6): 531-41, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21339169

RESUMO

The substitution of milk fat with virgin coconut oil (VCO) was used to produce nutritious ice cream with pleasant coconut flavor and aroma. Three formulations were developed whereby formulation VCO4, VCO8 and VCO12 was substituted with 4%, 8% and 12% of VCO, respectively. The physicochemical properties of ice creams analyzed include overrun, meltdown, pH, titratable acidity, total solid, protein and fat content. The fatty acids profile of VCO formulated ice creams and their stabilities over 3 and 6 weeks storage were studied respectively using gas chromatography (GC). Qualitative descriptive analysis (QDA) and consumer affective test were performed among the trained and untrained panelists. Significant differences (p < 0.05) of overrun, pH, total solid, protein and fat content between ice cream formulations were observed except titratable acidity. Increased VCO content in ice cream formulations lowered the melting resistance of ice cream. For GC analysis, the major fatty acid identified was lauric acid. Upon storage time, the concentration of unsaturated fatty acid decreased but the concentration of saturated fatty acid increased. The result of QDA showed that formulation VCO4, VCO8 and VCO12 were significantly (p < 0.05) different in attributes of color, firmness and smoothness as compared to the control ice cream. Formulation VCO12 was highly accepted by panelists in terms of the acceptance level of appearance, aroma, texture, flavor and overall acceptability. Hence, it has a potential marketable value.


Assuntos
Sorvetes/análise , Óleos de Plantas/química , Fenômenos Químicos , Óleo de Coco , Cor , Comportamento do Consumidor , Dieta com Restrição de Gorduras , Gorduras na Dieta/análise , Proteínas Alimentares/análise , Ácidos Graxos/análise , Manipulação de Alimentos , Preferências Alimentares , Humanos , Concentração de Íons de Hidrogênio , Malásia , Sensação , Fatores de Tempo , Temperatura de Transição
2.
Free Radic Biol Med ; 35(5): 540-7, 2003 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-12927603

RESUMO

Though increasing lines of evidence suggest that iron accumulation and iron-induced oxidative stress might be important pathological factors responsible for substantia nigra (SN) cell death in Parkinson's disease (PD), it is still unknown whether iron accumulation is a primary cause or consequence of nigral cell death. Using nuclear microscopy, iron histochemistry, TUNEL method for apoptosis detection, and tyrosine hydroxylase (TH) immunohistochemistry, the present study investigated possible changes in iron contents in the SN and correlations of dopaminergic cell death progression with the process of iron accumulation in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced parkinsonian monkey from 1 d to 18 months after MPTP administration. Our study demonstrated that apoptosis occurred in the ipsilateral SN at 1 d after MPTP injection and the number of TH-positive cells decreased significantly from 1 week onward. However, iron content was significantly increased in the ipsilateral SN from 4.5 months to 18 months after MPTP injection, and the iron increase was significantly correlated to the extent of dopaminergic cell death. These results suggest that dopaminergic cell death induced by MPTP administration might lead to iron accumulation in the monkey SN, and increased iron might contribute to the progression of nigral degeneration.


Assuntos
Apoptose/efeitos dos fármacos , Dopamina/metabolismo , Ferro/metabolismo , Doença de Parkinson Secundária/patologia , Substância Negra/patologia , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Animais , Núcleo Celular/metabolismo , Dopaminérgicos/farmacologia , Marcação In Situ das Extremidades Cortadas , Macaca fascicularis , Microinjeções , Degeneração Neural , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/metabolismo , Substância Negra/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
3.
J Comp Neurol ; 222(2): 161-5, 1984 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-6699205

RESUMO

The composition of the cervical sympathetic trunk (CST) in the cat is still not completely understood. The present study investigates, by the horseradish peroxidase (HRP) method of tracing neuronal connections, the presence of postganglionic and sensory neurons projecting via the CST. Following sympathectomy at the midcervical level and the application of HRP crystals to the cut ends of the CST which had been isolated from the surrounding by a 1.5% solution of agar-agar, labelled neurons were seen in the superior cervical (SCG), stellate (SG), inferior vagal ganglia (IVG), and spinal ganglia C8-T8. The maximum number of labelled neurons was 536 in the SCG, 460 in the SG, 180 in the IVG, and 104 in spinal ganglia C8-T8.


Assuntos
Axônios/fisiologia , Gânglios/fisiologia , Neurônios Aferentes/fisiologia , Sistema Nervoso Simpático/fisiologia , Animais , Gatos , Feminino , Peroxidase do Rábano Silvestre , Masculino , Pescoço/inervação , Vias Neurais/fisiologia
4.
J Comp Neurol ; 214(1): 79-86, 1983 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-6841678

RESUMO

This investigation describes the origin of the rubrospinal tract in neonatal (1-10 days old), developing (15-20 days old), and mature (2-4 months old) rats studied by using the horseradish peroxidase (HRP) method of tracing neuronal connections. HRP was administered in the cervical or lumbosacral segments of the spinal cord either in the crystal or solution form. The results showed that the rubrospinal tract extended to the lumbosacral part of the spinal cord at birth. There appeared to be no difference in the pattern of labelled rubrospinal (RS) neurons following the administration of HRP in the cervical or the lumbosacral cord segment of the neonatal, developing, and mature rats. In rats of these three age groups, labelled neurons were found bilaterally in the red nucleus, with a contralateral predominance, and they were found in both the parvicellular and magnocellular portions of the red nucleus. There was a somatotopic arrangement in the labelled RS neurons: Those projecting to the cervical cord segments were located in the dorsal and dorsomedial regions of the red nucleus and those projecting to the lumbosacral cord segments were located in the ventral and ventrolateral regions of the nucleus.


Assuntos
Núcleo Rubro/anatomia & histologia , Medula Espinal/anatomia & histologia , Fatores Etários , Animais , Animais Recém-Nascidos/anatomia & histologia , Tratos Extrapiramidais/anatomia & histologia , Ratos
5.
J Comp Neurol ; 228(1): 1-17, 1984 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-6434598

RESUMO

Following horseradish peroxidase injection into the cervical and lumbosacral cords of adult albino rats, labeled neurons were seen in the first cervical segment, brain stem, and cerebellar and diencephalic nuclei. A new pathway, the faciospinal projection, originating in the medial portion of the rostral part of the facial nucleus, was traced. Another new pathway, the olivospinal pathway, is probably also present. Our results for neurons projecting to the spinal cord (spinal-projecting neurons) from the nucleus ambiuus, dorsal motor nucleus of the vagus, superior vestibular nucleus and nucleus f, nucleus Darshevch, nucleus Rolleri, nucleus prepositus hypoglossi, and nucleus of the posterior commissure have been reported before in other mammals but not in rats. Projections from the following regions are in general agreement with previous results in rats, but show significant topographical differences: the first cervical segment; nuclei gracilis, cuneatus, and cuneatus lateralis; the midline and lateral reticular nuclear complex; the trigeminal nuclear complex (spinal, principal, and mesencephalic); nucleus of the tractus solitarius; the medial, lateral, and descending vestibular nuclei, nuclei coeruleus and subcoeruleus; superior colliculus; interstitial nucleus of Cajal, and the deep cerebellar nuclei. The distribution of labeled neurons in the nucleus parabrachialis, nucleus tegmentolaterodorsalis, nucleus Kölliker-Fuse, nucleus Edinger-Westphal, and the hypothalamic nuclear complex confirmed that of previous reports in rats. With the exception of a few nuclear groups which project primarily to either lumbosacral (e.g., the paraventricular nucleus of the hypothalamus) or cervical segments (e.g., the facial motor nucleus and the superior colliculus) most of the other nuclear groups project to both the lumbar and cervical levels. There is no distinct somatotopy in the neuronal groups projecting to both cervical and lumbosacral levels. With only a few exceptions (e.g., the superior vestibular nucleus) most of the spinal-projecting neurons are bilaterally distributed, some with contralateral and others with ipsilateral predominance.


Assuntos
Encéfalo/anatomia & histologia , Medula Espinal/anatomia & histologia , Animais , Gatos , Nervo Facial/anatomia & histologia , Haplorrinos , Vias Neurais/anatomia & histologia , Núcleo Olivar/anatomia & histologia , Núcleos da Rafe/anatomia & histologia , Ratos , Formação Reticular/anatomia & histologia , Especificidade da Espécie , Núcleos do Trigêmeo/anatomia & histologia , Núcleos Vestibulares/anatomia & histologia
6.
J Comp Neurol ; 228(1): 18-23, 1984 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-6480907

RESUMO

According to results from the horseradish peroxidase (HRP) method of tracing neuronal connections, the spinal cords of neonatal and immature rats receive a large number of descending projections from the first cervical cord segment, various brain-stem nuclei, and deep cerebellar and diencephalic nuclei. All these projections are present at birth, though at this age some of them are not fully established. Thus, only a few cells in the trigeminospinal, solitariospinal, tectospinal, and cerebellospinal groups were labeled after HRP injection in the lumbosacral or cervical cord segments in neonatal animals. They were clearly labeled in older, immature animals. The labeled neurons in other descending pathways appeared to be equal in density in neonatal, immature, and adult rats. This visual impression was stregthened by the counts of neurons in the interstitial nucleus of Cajal, which showed no significant difference in the number of labeled neurons in the three age groups. However, counts of labeled cells in the lateral vestibular nucleus and nucleus of the posterior commissure showed that there is a steady rise in the number of labeled neurons as the animals increase in age.


Assuntos
Encéfalo/anatomia & histologia , Medula Espinal/anatomia & histologia , Animais , Animais Recém-Nascidos , Núcleos Cerebelares/anatomia & histologia , Nervo Facial/anatomia & histologia , Vias Neurais/anatomia & histologia , Ponte/anatomia & histologia , Ratos , Colículos Superiores/anatomia & histologia
7.
Neuroscience ; 91(2): 579-85, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10366015

RESUMO

Parkinson's disease is a neurodegenerative disease characterized by dopaminergic cell death in the substantia nigra. The cause of the cell death is, however, obscure. Recently, accumulation of iron in the parkinsonian substantia nigra and iron-catalysed free radical generation have been proposed as possible causes of nigral cell death. The transferrin receptor has been implicated as a possible mediator of this iron accumulation in the parkinsonian substantia nigra. The present study investigated the distribution of transferrin receptor-immunoreactive proteins and its co-localization with tyrosine hydroxylase in the normal rat substantia nigra and their expressions in the parkinsonian substantia nigra from three days to three months after 6-hydroxydopamine lesioning. Computer image analysis of the grey mean of transferrin receptor staining in the microvessels was also employed. The results showed that the transferrin receptor immunolabelling was localized in some neurons and glial cells in the normal substantia nigra pars compacta and pars reticulata, and that about 54% of tyrosine hydroxylase-positive cells were also stained with transferrin receptor. There was a decrease of tyrosine hydroxylase- and transferrin receptor-positive cells in the 6-hydroxydopamine-lesioned substantia nigra. The grey mean of transferrin receptor staining in microvessels in the lesioned substantia nigra was, however, not different from that in the control. It was concluded that transferrin receptors in neurons, glial cells and microvessels might not be responsible for iron accumulation in the parkinsonian substantia nigra. The loss of transferrin receptor-immunopositive cells might, however, partly be accounted for by the death of transferrin receptor-positive dopaminergic cells induced by 6-hydroxydopamine lesioning.


Assuntos
Regulação da Expressão Gênica , Doença de Parkinson Secundária/metabolismo , Receptores da Transferrina/genética , Substância Negra/metabolismo , Animais , Lateralidade Funcional , Regulação da Expressão Gênica/efeitos dos fármacos , Imuno-Histoquímica , Masculino , Oxidopamina/toxicidade , Doença de Parkinson Secundária/induzido quimicamente , Ratos , Ratos Sprague-Dawley , Receptores da Transferrina/metabolismo , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo
8.
Neuroscience ; 67(3): 697-702, 1995 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7545797

RESUMO

Nitric oxide synthase activities in the facial motor nucleus were studied in rats after unilateral compression of the facial nerve. Using a radiometric assay which measured the total soluble nitric oxide synthase activities in the facial motor nucleus and the surrounding tissues, it was found that nitric oxide synthase activities were markedly increased during facial paralysis that resulted from compression of the facial nerve. The subsequent decrease in nitric oxide synthase activities between postoperative days 20 and 40 coincided with the recovery of facial functions. In contrast, staining with NADPH-diaphorase histochemistry revealed that the diaphorase activities in the facial motor neurons were markedly increased between days 20-40 when the total activities as measured biochemically were in decline. However, staining of the vascular endothelium was increased on postoperative day 7 when the total activity was high. It is suggested that the increase in total nitric oxide synthase activities immediately after facial nerve compression may be predominantly endothelial. Since the increase in neuronal NADPH-diaphorase reactivity coincided with the recovery of facial functions, increased neuronal nitric oxide synthase may be a contributing factor to the restoration of facial innervation. The results of this study show that biochemical measurements of soluble nitric oxide synthase activities in tissue homogenates and NADPH-diaphorase histochemical staining in tissue sections may represent two distinct populations of nitric oxide synthase.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Aminoácido Oxirredutases/metabolismo , Nervo Facial/fisiologia , Neurônios Motores/fisiologia , Animais , Paralisia Facial , NADPH Desidrogenase/metabolismo , Óxido Nítrico Sintase , Ratos , Ratos Wistar , Coloração e Rotulagem , Fatores de Tempo
9.
Neuroscience ; 90(3): 913-22, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10218791

RESUMO

Apolipoprotein D gene and protein expression were investigated in the rat brain and cerebellum, respectively, during development. Apolipoprotein D gene expression was first observed in embryonic day 12 rat brain, with a moderate increase in apolipoprotein D messenger RNA levels towards the later part (embryonic days 15-17) of gestation. In the postnatal rat brain, a marked induction of apolipoprotein D messenger RNA occurred at postnatal day 10, with progressively higher levels of apolipoprotein D messenger RNA observed up to postnatal day 20. Somewhat lower, but none the less high, levels of apolipoprotein D messenger RNA continued to be present in brains of adult animals. In the immature cerebellum (day 3 up to one- to two-week-old rats), there were many densely labeled apolipoprotein D-immunoreactive cells that had features of oligodendrocyte precursors. Purkinje neurons showed apolipoprotein D immunoreactivity in one- to two-week-old animals, after which there appeared to be some decrease in staining. Oligodendrocytes in the cerebella of two-week-old animals were strongly apolipoprotein D positive, with immunoreactivity declining in older animals. These results reveal a maturation-associated induction of apolipoprotein D gene expression in the rat brain, and expression of apolipoprotein D in glial (immature oligodendrocyte) cells in the immature cerebellum, followed by specific expression of apolipoprotein D in Purkinje neurons.


Assuntos
Envelhecimento/metabolismo , Animais Recém-Nascidos/metabolismo , Apolipoproteínas/genética , Apolipoproteínas/metabolismo , Encéfalo/fisiologia , Cerebelo/metabolismo , Expressão Gênica/fisiologia , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Apolipoproteínas D , Northern Blotting , Cerebelo/citologia , Cerebelo/ultraestrutura , Imuno-Histoquímica , Microscopia Eletrônica , Células de Purkinje/metabolismo , Células de Purkinje/ultraestrutura , Ratos , Ratos Sprague-Dawley
10.
Histol Histopathol ; 12(1): 85-97, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9046047

RESUMO

Blood vessels in frontal and temporal cerebral cortex of adults and two infants aged 5 months and 5 years were studied by electron microscopy. The cells outside the endothelium were classified on their ultrastructural characteristics. Fibroblasts had prominent rough endoplasmic reticulum and few mitochondria in the cytoplasm. They were different from pericytes, which contained a prominent Golgi apparatus but only a few, isolated profiles of rough endoplasmic reticulum. Smooth muscle cells were distinguished from fibroblasts and pericytes by the presence of filaments and caveolae. Perivascular cells were characterised by the presence of lysosomes and granules of different sizes and electron densities, and were present at all ages studied. Plasma cells had abundant rough endoplasmic reticulum in the cytoplasm, and were present only in the 5-month-old infant cortex. Cortical vessel diameter increased with age.


Assuntos
Vasos Sanguíneos/ultraestrutura , Córtex Cerebral/irrigação sanguínea , Córtex Cerebral/ultraestrutura , Adulto , Endotélio Vascular/ultraestrutura , Feminino , Fibroblastos/ultraestrutura , Humanos , Lactente , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Músculo Liso Vascular/ultraestrutura , Plasmócitos/ultraestrutura
11.
Neuroreport ; 10(10): 2067-71, 1999 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-10424676

RESUMO

The aim of this study was to determine whether neurotrophic factors such as brain derived neurotrophic factor (BDNF) and neurotrophin 3 (NT-3) would protect auditory hair cells from ototoxicity by aminoglycoside antibiotic. Twenty-seven Wistar guinea pigs were divided into three groups of nine animals each. BDNF and NT-3 (100 microg/ml) were delivered into the right scala tympani of guinea pig cochlea through a cannula-osmotic pump device. Artificial perilymph (AP) was used as control. Immediately after implantation of the device, each animal was given five successive doses of kanamycin (400 mg/kg). At 15, 30 and 60 days after infusion, surviving inner and outer hair cells were counted at each turn of every cochlea with a Philips 515 scanning electron microscope. Multiple comparison tests were carried out among the groups, using ANOVA and Dunnett T3/Tukey HSD. Protective effects of NT-3 on hair cells were observed at 30 and 60 days after kanamycin injection. BDNF had no protective effect on hair cells at 15 and 60 days, but some at 30 days. This study suggests that NT-3 and BDNF may protect against cochlear hair cell damage caused by kanamycin treatment. Possible mechanisms for the otoprotective effects were discussed. No single mechanism postulated can explain fully the results seen in this study. It is possible that the mechanisms act in concert to produce the observed effects, or there are as yet undiscovered mechanisms or secondary messengers responsible for the otoprotective effects.


Assuntos
Antibacterianos/farmacologia , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Células Ciliadas Auditivas Internas/efeitos dos fármacos , Células Ciliadas Auditivas Externas/efeitos dos fármacos , Canamicina/farmacologia , Fatores de Crescimento Neural/farmacologia , Análise de Variância , Animais , Sobrevivência Celular/efeitos dos fármacos , Feminino , Cobaias , Células Ciliadas Auditivas Internas/patologia , Células Ciliadas Auditivas Externas/patologia , Bombas de Infusão Implantáveis , Masculino , Microscopia Eletrônica de Varredura , Neurotrofina 3 , Pressão Osmótica
12.
J Neurosci Methods ; 32(1): 15-23, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2186224

RESUMO

Fast blue, true blue and fluorogold injected into neonatal and subadult rats via subcutaneous or intraperitoneal route labelled certain forebrain nuclei and the central and peripheral neurons whose axons form the spinal and most cranial nerves. The A1 and A5 noradrenergic neurons, nucleus of the tractus solitarius and some neurons in the nucleus raphe medianus, nucleus reticularis gigantocellularis were also labelled. In addition, occasional fluorescent neurons were seen in the vestibular nucleus, locus coeruleus, fastigial nucleus and Purkinje cell layer of the cerebellum. Some nuclei labelled in neonatal rats hardly showed any labelled neurons in subadult rats. After injection the subarachnoid space, blood vessels in the spinal cord, brain and peripheral ganglia, the circumventricular organs and the choroid plexuses were labelled much faster than the neurons. A similar pattern of labelling was seen in subadult rats receiving intravenous injection of fluorogold. Evans blue and rhodamine injected intravenously failed to label any neurons in the brain or spinal cord.


Assuntos
Encéfalo/anatomia & histologia , Corantes Fluorescentes , Técnicas Histológicas , Estilbamidinas , Amidinas , Animais , Benzofuranos , Encéfalo/citologia , Corantes Fluorescentes/administração & dosagem , Corantes Fluorescentes/farmacocinética , Injeções Intraperitoneais , Injeções Intravenosas , Injeções Subcutâneas , Neurônios , Ratos
13.
Brain Res ; 265(1): 1-9, 1983 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-6850310

RESUMO

Following the administration of horseradish peroxidase (HRP) in the middle or lower cervical cord segments of neonatal (1-10 days), developing (15-20 days) and mature (2-4 months) albino rats, labeled pyramidal neurons were found in layer V of the cerebral cortex. They formed one continuous band of labeled neurons in the frontal and parietal isocortex in neonatal animals. The band began close to the frontal pole and extended distally for about 3600 microns. Mediolaterally the lateral limit of the band was at the dorsal lip of the rhinal sulcus. Neurons in the 'shoulder' region along the medial surface of the cerebral hemisphere were also labeled. As the animals increased in age it became increasingly more difficult to label the pyramidal neurons in the parietal band. The band appeared broken and discontinuous in the parietal region in the 15-day-old rats. In the 20-day-old and mature rats the labeled neurons appeared in two bands, a dorsolateral one and a parietal one, the two being separated by a variable gap of cortex where practically no or very few neurons were labeled. Labeled neurons in the 'shoulder' region were distinctly seen only in the rostral region of the frontal isocortex in older animals. Following the administration of HRP in lumbosacral cord segments, no labeled layer V pyramidal neurons were seen in the 2-day-old rats, but they were seen to form one continuous band in the dorsolateral part of the cerebral cortex in rats aged 5 days postnatally and older. They appeared in a caudo-rostral sequence, with neurons in the caudal part of the cerebral cortex projecting to the more caudal cord segments and those in the frontal part to the more rostral cord segments. Mediolaterally the band was about 2 mm wide. Neurons in the 'shoulder' region were infrequently seen in neonatal and developing animals.


Assuntos
Tratos Piramidais/anatomia & histologia , Animais , Animais Recém-Nascidos/anatomia & histologia , Mapeamento Encefálico/métodos , Peroxidase do Rábano Silvestre , Tratos Piramidais/crescimento & desenvolvimento , Ratos
14.
Brain Res ; 194(2): 299-310, 1980 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-7388616

RESUMO

The present study shows that 3--5 days following lesions of the dentate and interposed nuclei in normal adult rats degenerating axons and axon terminals can be detected in the contralateral pontine gray. The degenerating axon terminals form Gray's type I axo-dendritic contacts with fine and intermediate dendrites measuring between 0.8--2.4 microns. The present study also investigates, by electron microscopy, the synaptic rearrangement of the sensorimotor corticopontine projections following neonatal left cerebellar hemispherectomy. Following neonatal left cerebellar hemispherectomy, the right sensorimotor and adjacent cortex (SMC) presents a very dense ipsilateral and a modest amount of contralateral corticopontine projections in contrast with a predominantly ipsilateral corticopontine projection seen in the normal adult rat. As with the ipsilateral corticopontine projection seen in the normal adult animal, the bilateral corticopontine projections seen in the experimental animals form contacts with dendrites suggestive of Gray's type I synapses. While the corticopontine projections in normal control animals form synapses with fine dendrites measuring 0.2--1.2 micron the corticopontine projections in the experimental animals form synaptic relations with fine dendrites and with intermediate dendrites measuring 0.2--2.4 microns. As the normal cerebellopontine fibers from the dentate and interposed nuclei also form axo-dendritic synapses on fine and intermediate dendrites and the contracts formed are also of Gray's type I synapses, it is possible that some of the newly formed corticopontine fibers in the experimental animals might have replaced the cerebellopontine fibers synapsing on intermediate dendrites. Synaptic rearrangement appears to take place as suggested by the presence of synaptic complexes in which one axon terminal contacts two or more dendrites or two or more axon terminals contact one dendrite. Such complexes are frequently seen to undergo degeneration following the right SMC lesion in the experimental animals. Other complex synaptic structures are also present in both the right and left pontine gray in the experimental animals. They are not seen to undergo degeneration following the right SMC lesions. Occasional features of neuronal reaction could still be seen in both sides of the pontine gray for as long as 3--6 months after the neonatal cerebellar lesions.


Assuntos
Cerebelo/fisiologia , Córtex Cerebral/anatomia & histologia , Regeneração Nervosa , Ponte/anatomia & histologia , Vias Aferentes/anatomia & histologia , Vias Aferentes/fisiologia , Animais , Animais Recém-Nascidos , Axônios/ultraestrutura , Dendritos/ultraestrutura , Dominância Cerebral/fisiologia , Microscopia Eletrônica , Degeneração Neural , Ratos , Córtex Somatossensorial/anatomia & histologia , Sinapses/ultraestrutura
15.
Brain Res ; 107(1): 1-8, 1976 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-1268714

RESUMO

The present study confirms the suggestive evidence brought forth by the finding of Leong and Lund. Following neonatal lesion of the sensorimotor and adjacent cortex of the albino rats, the remaining intact contralateral cortex projects bilaterally to the superior colliculus, pons and spinal cord, all of which normally receive a unilateral corticofugal projection. Like the normal projections to the 3 areas studied, the anomalous projections form Gray's type I axo-dendritic relations. The terminals of the anomalous projections seem to form a more complex configuration with one axon terminal synapsing on more dendrites than is usual.


Assuntos
Córtex Cerebral/fisiologia , Ponte/ultraestrutura , Medula Espinal/ultraestrutura , Colículos Superiores/ultraestrutura , Sinapses/ultraestrutura , Animais , Animais Recém-Nascidos , Axônios/ultraestrutura , Dendritos/ultraestrutura , Lateralidade Funcional , Degeneração Neural , Vias Neurais , Ratos , Córtex Somatossensorial/fisiologia , Vesículas Sinápticas/ultraestrutura
16.
Brain Res ; 310(2): 311-23, 1984 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-6488022

RESUMO

Our study shows that, using Elliott's method, 6 major groups of neurons can be identified in the lumbosacral cord segments of both monkeys and rats. These are the medial (m), ventromedial (vm) anterolateral (al), central (c), posterolateral (pl) and post-posterolateral (ppl) groups; they are, except for minor differences, similarly arranged in neonatal, immature, and mature monkeys and rats. Localization of neurons by the horseradish peroxidase method reveals that the sciatic nerve (ScN) neurons are distributed to L4-L7 segments in all monkeys studied and also to the rostral part of S1 segment in some monkeys. They occur in the ppl, pl, c and al groups. Of the ScN neurons, the common peroneal nerve (CPN) neurons occur more peripherally and slightly more rostrally than the tibial nerve (TN) neurons. ScN neurons in rats extend between the caudal parts of L3 and L6 segments but may extend to the rostral part of S1 segment. Their distribution to the ppl, pl, c and al groups resembles that in the monkey except for minor differences. The distribution of CPN and TN neurons in the ScN neurons in the rat also resembles that in the monkey. The distribution of ScN neurons is similar in the neonatal, immature and mature rats and monkeys except for minor differences. Femoral nerve (FN) neurons in both monkeys and rats extend between L2 and L4 segments. However, in monkeys, FN neurons start to appear only in the caudal part of L2 segment and may extend to the rostral part of L5 segment. In rats, they appear in the rostral part of L2 segment and end about the middle of L4 segment. In both rats and monkeys, FN neurons occur in the al, pl and c groups; in in addition they also occur in the ppl group in the monkey. There is minor difference in the distribution of FN neurons in the al, pl and c groups in both rats and monkeys. There is postnatal growth in length of the spinal segments containing ScN neurons in both rats and monkeys, but no significant difference in the number of labeled ScN neurons in the neonatal, immature and mature rats and monkeys. There is also no significant difference in the counts of labeled right and left ScN neurons. The histograms showing the number of labeled ScN neurons against their diameters are very similar in both rats and monkeys. In both animals, the diameters of ScN neurons vary widely between 3 and 53 microns.


Assuntos
Medula Espinal/anatomia & histologia , Nervos Espinhais/anatomia & histologia , Animais , Animais Recém-Nascidos , Células do Corno Anterior , Nervo Femoral/anatomia & histologia , Macaca fascicularis , Nervo Fibular/anatomia & histologia , Ratos , Nervo Isquiático/anatomia & histologia , Nervo Tibial/anatomia & histologia
17.
Brain Res ; 223(2): 386-90, 1981 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-6169407

RESUMO

Following injection of horseradish peroxidase (HRP) solution in the gastrocnemius muscle or the extensor digitorum longus muscle in neonatal and developing albino rats, some neurones in the cervical enlargement, mid-thoracic region and sacral region were labelled in addition to the region of the spinal cord from where the sciatic nerves emerged. The labelling was most probably the result of diffusion of HRP solution from the site of injection to nearby structures.


Assuntos
Músculos/inervação , Neurônios/fisiologia , Medula Espinal/fisiologia , Envelhecimento , Animais , Animais Recém-Nascidos , Transporte Axonal , Peroxidase do Rábano Silvestre , Desenvolvimento Muscular , Ratos , Medula Espinal/crescimento & desenvolvimento
18.
Brain Res ; 858(1): 163-6, 2000 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-10700609

RESUMO

The pathologic hallmark of Parkinson's disease is the dopaminergic cell death in the substantia nigra (SN). The cause of the cell death is, however, unknown. Even the question on whether the cells die by apoptosis or necrosis has not been answered with certainty. In 6-Hydroxydopamine induced Parkinsonian rats, the present study observed apoptotic nuclei from 1 day to 14 days after lesioning, using the TdT(terminal deoxynucleotidyl transferase)-mediated dUTP-biotin nick-end labeling method. Tyrosine hydroxylase immunohistochemistry and haematoxylin staining further revealed that these apoptotic cells are dopaminergic cells in the substantia nigra. The results suggest that dopaminergic cells in SN undergo apoptosis in the rat model of Parkinson's disease.


Assuntos
Apoptose , Dopamina/metabolismo , Doença de Parkinson Secundária/patologia , Substância Negra/metabolismo , Substância Negra/patologia , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/enzimologia , Núcleo Celular/patologia , Modelos Animais de Doenças , Imuno-Histoquímica , Marcação In Situ das Extremidades Cortadas , Masculino , Oxidopamina , Doença de Parkinson Secundária/induzido quimicamente , Doença de Parkinson Secundária/enzimologia , Ratos , Ratos Sprague-Dawley , Substância Negra/efeitos dos fármacos , Tirosina 3-Mono-Oxigenase/metabolismo
19.
Brain Res ; 808(1): 23-30, 1998 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-9795113

RESUMO

In the present study, immunohistochemical stainings for OX-6, OX-42, nitric oxide synthase I and II as well as nitrotyrosine were used to investigate possible correlation among microglial reactivity, nitric oxide synthase upregulation, peroxynitrite involvement and neuronal death in the nucleus dorsalis and red nucleus following lower thoracic spinal cord hemisection. Significant neuronal loss was found in the ipsilateral nucleus dorsalis and contralateral red nucleus after cord hemisection. A distinctive microglial reaction for OX-42 could be observed from one to four weeks post axotomy in the ipsilateral nucleus dorsalis; by contrast, it was observed on both sides of the red nucleus from one to three weeks following cord hemisection. The activated microglial cells showed some degree of hypertrophy. From the microglial immunoreactivity as well as their appearance, it was speculated that microglial activation might be beneficial or protective to the axotomized neurons. In normal and sham-operated rats, neurons of the nucleus dorsalis were not nitric oxide synthase I reactive. Three weeks after cord hemisection, neurons in the ipsilateral nucleus dorsalis below the lesion showed strong immunoreactivity. Neurons in the red nucleus that normally displayed weak nitric oxide synthase I immunoreactivity showed an increase on both sides of the nucleus. These results suggested that nitric oxide synthase I expression in the nucleus dorsalis following axotomy was synthesized de novo and might act as a neurotoxic agent. However, the bilateral increase in expression of nitric oxide synthase I in the red nucleus after lower thoracic cord hemisection was due to up-regulation of the constitutive enzyme and might have some neuroprotective function. Our results also suggested that peroxynitrite played no or little role in the neurodegeneration in the nucleus dorsalis and red nucleus following axotomy.


Assuntos
Antígenos CD , Antígenos de Neoplasias , Proteínas Aviárias , Proteínas Sanguíneas , Microglia/fisiologia , Óxido Nítrico Sintase/metabolismo , Núcleo Rubro/fisiopatologia , Traumatismos da Medula Espinal/fisiopatologia , Medula Espinal/fisiologia , Tegmento Mesencefálico/fisiopatologia , Animais , Anticorpos Monoclonais/análise , Antígenos de Superfície/análise , Basigina , Lateralidade Funcional , Regulação Enzimológica da Expressão Gênica , Imuno-Histoquímica , Masculino , Glicoproteínas de Membrana/análise , Microglia/patologia , Degeneração Neural/patologia , Neurônios/patologia , Óxido Nítrico Sintase/análise , Ratos , Ratos Wistar , Núcleo Rubro/enzimologia , Núcleo Rubro/patologia , Traumatismos da Medula Espinal/enzimologia , Traumatismos da Medula Espinal/patologia , Tegmento Mesencefálico/enzimologia , Tegmento Mesencefálico/patologia , Tirosina/análogos & derivados , Tirosina/metabolismo
20.
Brain Res ; 560(1-2): 50-4, 1991 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-1760746

RESUMO

The middle three-fifths of the forebrains of 14-day-old embryos were obtained and transplanted into the cortical cavities of adult rats made 7 days prior to the transplantation. The expression of proteins, as revealed by 2-dimensional gel electrophoresis studies, and the activities of energy metabolizing enzymes in the mature allografts were compared with those in the 14-day-old embryonic forebrains and corresponding areas in the contralateral cerebral hemispheres of the hosts. They were shown to approach adult pattern and adult values after 10-12 weeks of growth. The biochemical findings were discussed and correlated with some of the anatomical observations.


Assuntos
Transplante de Tecido Encefálico , Encéfalo/metabolismo , Transplante de Tecido Fetal , Proteínas do Tecido Nervoso/metabolismo , Animais , Encéfalo/embriologia , Metabolismo Energético , Masculino , Ratos , Ratos Endogâmicos , Fatores de Tempo
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