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1.
Age-related histological changes in the canine substantia nigra   总被引：2，自引：0，他引：2  
Age-related changes in the canine substantia nigra, were examined using immunostaining for tyrosine hydroxylase (TH), glial fibrillary acidic protein (GFAP), neurofilament (NF), ubiquitin, single stranded DNA (ssDNA), and alpha-synuclein (alphaSN). Brain sections from 34 necropsied dogs, ranging from 2 months to 18 years old, were used for this study. On general histological examinations, several age-related changes, including lipofuscin deposition, polyglucosan bodies, amorphous basophilic inclusions and eosinophilic crystal inclusions, were found in the aged dogs. Immunohistochemically, TH-positive neurons were located only in the substantia nigra. The number of TH-positive neurons was well preserved in all dogs examined, however, the ratio of TH-positive neurons to GFAP-positive glial cells tended to show slight decrease in aged dogs. By ssDNA immunostaining for apoptotic cells, there were no significant results in the number of ssDNA-positive neurons. The number of ubiquitin- and NF-positive swollen neurites was increased markedly in aged dogs. Ubiquitin immunostaining revealed a small number of basophilic and eosinophilic inclusions, although both types of inclusions were negative for NF. By alphaSN immunostaining, no neurons were immunoreactive and no basophilic or eosinophilic intracytoplasmic inclusions were revealed. These results indicate that in the substantia nigra of aged dogs the dopaminergic neurons are well preserved, but intracytoplasmic inclusions and ubiquitin-positive degenerative neurites are commonly found.  相似文献   

2.
The pattern of astrocytic gliosis (AG) was examined in 2-month-old to 18-year-old dogs using glial fibrillary acidic protein (GFAP) immunohistochemistry and electron microscopy. Coronal sections from various levels of the central nervous system (CNS) were stained with hematoxylin & eosin, Luxol Fast Blue, Nissl, and Bodian in addition to GFAP. A consistent pattern of age-related AG was observed in the dogs. The white matter, cortico-medullary junction, and subcortical nuclei in the cerebrum, central nuclei in the cerebellum, various nuclei in the brain stem, and grey matter of the spinal cord showed even and intense GFAP staining. AG was also prominent in the cerebral and cerebellar cortices and thalamus. Moderate AG was observed in the hippocampus and white matter of the cerebellum and spinal cord. Electron microscopy demonstrated increased number of profiles of degenerative neural components in the vicinity of hypertrophic astrocytes in the cerebral cortex of the aged dogs. Moderate to severe AG was consistently shown in the CNS of the aged dogs. In contrast, young normal dogs showed minimum amounts of GFAP-positive astrocytes in the CNS. These findings suggest that the observed AG in the CNS of the dogs is a morphological expression of aging.  相似文献   

3.
A granular cell tumor involving the pituitary gland, optic chiasm and ventral pyriform lobes was discovered in a 12-year-old Labrador Retriever. Clinical signs included acute blindness, seizures, ataxia, weakness, and behavioral changes. The diagnosis was established by histopathologic and ultrastructural examination of neoplastic tissues collected at necropsy. Granular cell tumors involving the central nervous system are well documented in humans but rarely have been described in dogs. The location of the neoplasm and the clinical symptoms seen in this dog closely parallel those of a rare syndrome in humans commonly described as symptomatic parasellar or pituitary granular cell tumors. The cell of origin for these tumors is still highly debated, and attempts to characterize human granular cell tumors through immunohistochemistry have produced conflicting results. An immunohistochemical profile of this neoplasm revealed focal positive staining for vimentin with a lack of staining for neuron-specific enolase, glial fibrillary acidic protein, S-100, and synaptophysin. All neoplastic cells were strongly positive with the periodic acid-Schiff reaction.  相似文献   

4.
To distinguish age-related changes in hematology and clinical chemistry values from those resulting from disease, hematology, and clinical chemistry values of healthy, age-matched Beagle dogs 3 to 14 years of age were analyzed. Serum potassium, total protein and globulin concentration, and lactic dehydrogenase activity increased with age, while urea nitrogen, creatinine and albumin concentration, and gamma-glutamyl transferase activity decreased. The 12-year-old group had some distinct differences from the other age groups: glucose concentration was lower, alanine aminotransferase and aspartate aminotransferase activity and triglyceride concentration were higher. No significant age-related differences were found in the hematology parameters analyzed. This report extends the documented, age-related changes in normal Beagle dogs to 14 years of age. The age-related changes in organ-specific serum chemistries such as urea nitrogen and creatinine (kidney), and alanine aminotransferase (liver) noted here suggest that 12 years may be a pivotal age for determining longevity in the Beagle dog.  相似文献   

5.
Localization of metallothionein (MT) -I & -II and MT-III and its significance in the brain aging in dogs were examined using immunohistological and molecular pathological techniques. MT-I & -II immunohistochemistry showed positive staining in the hypertrophic astrocytes throughout the aged dog brains; these MT-I & -II immunoreactive astrocytes were predominant in the cerebral cortex and around the blood vessels in the brain. These findings dominated in the brain regions with severe age-related morphological changes. In situ hybridization using MT-I mRNA riboprobes also demonstrated signals for MT-I mRNA in these hypertrophic astrocytes. Immunohistochemistry using a guinea pig antiserum against a synthetic polypeptide of canine MT-III demonstrated positive MT-III immunoreactivity predominantly in neurons in the Zn-rich regions such as hippocampus and parahippocampus. The findings were supported by in situ hybridization using MT-III mRNA riboprobes. Both MT-III immunoreactivity and signals for MT-III mRNA were demonstrated in neurons in the brain regardless of the intensity of the age-related changes. These results suggest, first, MT-I & -II may be induced in relation to the progress of the age-related morphological changes in the brain, playing an important role in the protection of the brain tissue from the toxic insults responsible for the brain aging, and second, MT-III may play a role in maintenance of Zn-related essential functions of the brain.  相似文献   

6.
Lens displacement resulting in secondary glaucoma is common in terrier breeds. This study was carried out to evaluate whether light microscopy was useful in detecting abnormal patterns in zonular fiber protein. Eyes from 63 dogs with glaucoma secondary to lens displacement were evaluated for the presence of abnormal zonular fiber morphology using the following stains: hematoxylin and eosin, periodic acid Schiff (PAS), Masson's trichrome and Verhoeff's elastin stains. Two distinct forms of abnormal zonular fiber morphology were recognized and designated as zonular fiber dysplasia (ZFD) and zonular fiber collagenization (ZFC). ZFD protein morphology was characterized by being tightly adherent to the nonpigmented ciliary body epithelium, exhibiting a distinct lamellar and cross-hatched pattern and staining strongly positive with PAS and trichrome stains, and staining negative with elastin stains. ZFD was predominant in terrier breeds (18 of 29) and Shar-Pei dogs (4 of 29). ZFC abnormality was characterized by excessive zonular fiber that was not tightly adherent to the ciliary body epithelium and staining positive with PAS, trichrome (blue for collagen) and elastin stains. Only 7 of 19 dogs with ZFC changes were terrier breeds, and there was no pattern in the breeds affected. Fifteen of the 63 dogs used in the study had normal appearing zonular fibers. The staining pattern in these dogs matched normal controls by staining positive with PAS and Verhoeff's elastin stains and had only minimal positive staining with Masson's trichrome stain. Results suggest that light microscopy is useful in detecting breed-related changes in zonular fiber morphology in cases of glaucoma secondary to lens displacement. These changes may correlate with the presence of abnormal zonular fiber proteins and might be important in the pathogenesis of primary lens displacement in terrier and Shar-Pei dogs.  相似文献   

7.
A hereditary cerebellar degenerative disorder has emerged in Scottish Terriers. The aims of this study were to describe and quantify polyglucosan body accumulation and quantify Purkinje neurons in the cerebellum of affected and control dogs. The brains of 6 affected Scottish Terriers ranging in age from 8 to 15 years and 8 age-matched control dogs were examined histopathologically. Counts of Purkinje neurons and polyglucosan bodies were performed in control and affected dogs on cerebellar sections stained with periodic acid-Schiff. Affected dogs showed a significant loss of Purkinje neurons compared with control dogs (vermis: P < .0001; hemisphere: P = .0104). The degeneration was significantly more pronounced dorsally than ventrally (P < .0001). There were significantly more polyglucosan bodies in the ventral half of the vermis when compared with the dorsal half (P < .0001) in affected dogs. In addition, there were more polyglucosan bodies in the ventral half of the vermis in affected dogs than in control dogs (P = .0005). Polyglucosan bodies in all affected dogs stained positively with toluidine blue and alcian blue. Immunohistochemically, polyglucosan bodies in affected dogs were positive for neurofilament 200 kD and ubiquitin and negative for glial fibrillary acidic protein, synaptophysin, neurospecific enolase, vimentin, and S100; the bodies were negative for all antigens in control dogs. Ultrastructurally, polyglucosan bodies in 1 affected dog were non-membrane-bound, amorphous structures with a dense core. This study demonstrates significant Purkinje cell loss and increased polyglucosan bodies in the cerebellum of affected Scottish Terriers.  相似文献   

8.
The life expectancy of domestic pet cats is increasing, along with the occurrence of geriatric-onset behavioural problems, such as cognitive dysfunction syndrome (CDS). While the cause of CDS is unclear, it has been suggested that it may result from age-related neurodegeneration. In aged and in particular senile human beings, histopathological changes may include the extracellular accumulation of plaque-like deposits of beta-amyloid (Abeta) protein and the intracellular accumulation of an abnormally hyperphosphorylated form of the microtubule-associated protein, tau. In severe cases, the latter may form into neurofibrillary tangles. Brain material was assessed from 19 cats, aged from 16 weeks to 14 years; 17 of which had clinical signs of neurological dysfunction. Immunohistochemical methods were used to detect Abeta and its intracellular precursor protein (amyloid precursor protein (APP)) and hyperphosphorylated-tau. APP was constitutively expressed, with diffuse staining of neurons and blood vessels being detected in all cats. More intense staining and diffuse extracellular Abeta staining deposits were found within the deep cortical areas of the anterior- and occasionally mid-cerebrum of seven cats, all of which were over 10 years of age. Neurons staining intensely positive for AT8-immunoreactivity were seen in two cats, aged 11 and 13 years. However, no mature neurofibrillary tangles were detected. This study demonstrated that extracellular Abeta accumulation and AT8-immunoreactivity within neurons are age-related phenomena in cats, and that they can occur concurrently. There are similarities between these changes and those observed in the brains of aged people and other old mammals.  相似文献   

9.
The morphological features of iridociliary epithelial tumors in 100 dogs and 17 cats were reviewed. Twenty-seven cases were in either Golden Retrievers or Labrador Retrievers. Affected globes were stained for light microscopy with alcian blue, periodic acid Schiff (PAS) and hematoxylin and eosin stains. Selected tissues were examined by immunohistochemistry for vimentin, desmin, cytokeratin, S-100, neuron-specific enolase (NSE), and glial fibrillary acid protein (GFAP). The presence or absence of hyaluronic acid was recorded by staining with alcian blue before and after digestion of the tissue with hyaluronidase. Canine tumors were divided into papillary and solid tumors based on the pattern of growth. Twenty-eight of 57 papillary tumors exhibited invasive behavior including eight of the 57 which showed infiltration of the sclera. Twenty-nine of 43 solid tumors were invasive including 13 of 43 with scleral invasion. Tumors with scleral invasion were designated adenocarcinoma. Tumors of both types could be pigmented or nonpigmented and often contained smooth basement membranes reminiscent of the inner membrane of the nonpigmented ciliary body epithelial cell. All of the feline tumors were nonpigmented and 14 of 16 feline tumors were solid and two of the tumors were papillary. Eighteen of 20 canine tumors and three of four feline tumors stained positive for vimentin. Cytokeratin stain was positive only in a few of the highly aggressive tumors. The finding of pigmented epithelial cells, thick, smooth basement membrane structures, positive staining for vimentin, S-100, and NSE as well as hyaluronic acid deposition were considered to be features which define iridociliary epithelial tumors in dogs. The positive staining for vimentin and NSE are highly specific markers which help to characterize iridociliary epithelium and distinguish this tumor from metastatic epithelial tumors. The finding of solid nonpigmented tumors with small epithelial cells packeted by thin PAS-positive membranes staining positive for vimentin were considered significant features defining iridociliary epithelial tumors in cats. Follow-up information on survival and cause of death was obtained on 43 canine cases and only two feline cases. The average follow-up interval in dogs was 25 months and only two dogs died with lesions that could have been due to metastasis although neither was confirmed. We concluded that neither iridociliary adenomas nor adenocarcinomas is likely to metastasize.  相似文献   

10.
While aging studies employing a cross-sectional design have been informative in documenting many age-related alterations in immune function between different age cohorts within a population, longitudinal studies are invaluable for verifying changes at the level of the individual and for defining the precise periods of life during which particular changes occur. In the present study, a battery of immunological parameters were evaluated in a group of Labrador Retrievers as part of a comprehensive longitudinal aging study. Twenty-three dogs (14 females, 9 males; from 4 to 11 years of age) were evaluated annually for total WBC counts, lymphocyte subset distributions, natural killer cell activity and neutrophil phagocytic activity, and biannually for lymphoproliferative activity. An age-related decline in absolute numbers of lymphocytes, T-cells, CD4-cells and CD8-cells was observed in both genders. The distribution of lymphocyte subsets shifted with age, most dramatically in the females; percentages of B-cells declined while those of T-cells increased. Changes in percentages of CD4- and CD8-cells over the 8-year period were not dramatic; in females, percentages of CD8-cells increased significantly in early- to mid-life and then stabilized. Lymphoproliferative responses to mitogens declined over time in both genders. Males demonstrated higher levels of NK cytolytic activity than females; a marginal decline in activity with age was observed. No significant age-related changes in the phagocytic capacity of PMN were observed. These longitudinal findings help to discriminate between those immune parameters which change most dramatically in early-life versus those which either change more dramatically later in life or change gradually over the entire span of life. In addition they identify significant gender differences in several parameters and corroborate our previously published cross-sectional aging data in the same species.  相似文献   

11.
Accumulation of lipids and hyalinosis in the splenic arteries of aged dogs are frequently detected by routine histopathologic examinations. The purpose of this study was to pinpoint the localization of canine apolipoprotein B-100 (CApoB-100) and immunoglobulins (IgA, IgM, IgG) in the splenic arteries of aging dogs (n = 80) through the use of immunohistochemical techniques. CApoB-100 deposits were found in the subendothelial space, extracellular matrix, and atheromatous lesions in the tunica media of the arteries in dogs > or = 6 years of age. Foamy cytoplasm of the infiltrated macrophages was also CApoB-100 immunopositive. In dogs > or = 10 years of age, almost all central arteries were CApoB-100 immunopositive. Hyaline deposits within the wall were characterized by immunopositivity against canine IgA, IgM, IgG, and albumin. Lipid accumulation in splenic arteries may be an age-related lesion and a precursor of the atheromatous plaques associated with splenic hemorrhage and infarcts later in life. In addition, deposition of immunoglobulins, probably mediated by immune complexes, may play an important role in the development of canine vascular diseases similar to human disease.  相似文献   

12.
Lymphocyte populations in the synovial membranes of dogs with canine rheumatoid arthritis (CRA) were investigated by immunohistochemical staining techniques. T-lymphocytes were the predominant cell type distributed throughout the supporting layer of the synovial membranes. B-lymphocytes expressing IgG were seen far more commonly than those expressing either IgA or IgM. Synovial membrane biopsies from normal and osteoarthritic joints did not have the marked cellular infiltrates seen in joints with CRA. The synovial immunohistopathological features in dogs with CRA are similar to those seen in human rheumatoid arthritis.  相似文献   

13.
Sixteen choroid plexus (CP) tumors in 12 male and four female adult dogs were analyzed microscopically. Tumors were in the lateral (six), third (six), and fourth (four) ventricles. The average age of the dogs was 6 years. Tumors were classified by the following criteria: 1) choroid plexus papilloma (CPP), which resembled normal choroid plexus and had low mitotic activity; 2) choroid plexus papilloma (CPP), which resembled normal choroid plexus and had low mitotic activity; 2) choroid plexus papilloma with atypical features (atypical CPP), which had increased cellular density, nuclear atypia, two to four mitoses per 40x microscopic field, necrosis, and infiltration of the brain parenchyma and/or leptomeninges; and 3) choroid plexus carcinoma (CPC), which had marked nuclear atypia, poorly formed papillae, greater than four mitoses per 40x microscopic field, abnormal mitotic figures, and/or extraneural metastasis. The 16 tumors were classified either as CPP or atypical CPP (none as CPC). Statistically significant associations between brain infiltration and necrosis and atypical CPP were identified. Immunohistochemical studies in 11 tumors demonstrated staining for keratin in three tumors, two of which also reacted with carcinoembryonic antigen (CEA). There was no immunoreactivity with glial fibrillary acidic protein or epithelial membrane antigen. Choroid plexus from one of three control dogs stained focally for cytokeratin only. It is concluded that normal choroid plexus and CP tumors in the dog express epithelial, but not glial differentiation.  相似文献   

14.
To contribute to the existing body of knowledge in the literature on the apparently rare extramedullary plasmacytoma in cats, lymphoid tumors with plasmacytic cellular morphology taken from nine cats were examined. The paraffin-embedded material was investigated by standard hematoxylin and eosin, and special staining techniques (Giemsa, Congo-red, and periodic acid-Schiff reaction). The tumors also were examined immunohistochemically for the presence of immunoglobulin G, immunoglobulin A, immunoglobulin M, immunoglobulin light chains (lambda, kappa), various amyloid proteins, and FeLV-antigen (p27 protein). An immunoglobulin-producing tumor of plasmacellular origin (extramedullary plasmacytoma [EMP]) could be diagnosed in all cases on the basis of immunohistochemical light-chain expression. All but one of the neoplasms occurred in the skin of older, predominantly male cats. As in humans and dogs, the following types could be identified according to their morphologic features: mature type (two), cleaved type (two), asynchronous type (four), and polymorphous type (one). The tumor tissue of three cats revealed amyloid deposits, which were immunohistochemically diagnosed as ALlambda-amyloid in all three cases.  相似文献   

15.
OBJECTIVE: The aim of this study was to characterize the clinical and morphologic features of neuronal ceroid lipofuscinosis (NCL) in the Polish Owczarek Nizinny (PON) breed of dog. ANIMALS: Nine Swedish PON dogs of both sexes were included in the study. PROCEDURE: All dogs underwent a detailed clinical evaluation, with emphasis on ophthalmic exams. Histopathology and electron microscopy were performed on the eyes, brain and various internal organs. Immunohistochemical staining for detection of sphingolipid activator proteins (SAPs) and mitochondrial ATP synthase (SCMAS) was performed on the eyes and brain. RESULTS: The dogs showed behavioral abnormalities, motor disturbances and visual impairment or blindness. Pupillary responses were abnormal while fundus changes varied from normal to severe retinal atrophy. Electroretinography (ERG) showed variable changes, from slight alterations in the process of dark adaptation to severely reduced or nonrecordable ERG a- and b-wave amplitudes. Histopathology revealed intracytoplasmic storage bodies within neurons of the brain and in retinal cells, especially the retinal pigment epithelium (RPE). Round to oval granular type of inclusion bodies, known as granular osmiophilic dense deposits (GRODS), were found in neuronal cells in the brain and in the retina. Immunohistochemistry identified the storage material in the brain and retina as consisting of SAPs. CONCLUSION: The presently described NCL disease in PON dogs shows similarities to previously recorded cases in the Miniature Schnauzer. The closest human equivalent to this disease is infantile NCL (CLN1), in which the major stored proteins are SAPs and the ultrastructure of the inclusion bodies of neuronal cells is granular.  相似文献   

16.
Inclusion bodies, indistinguishable from rabies inclusion bodies (Negri bodies), were found in the brains of 8 nonrabid dogs. The inclusions were compared to Negri bodies present in neurons of rabies-positive animals and examined for the presence of rabies virus by a combination of immunoperoxidase staining (7 cases), fluorescent antibody (FA) staining (1 case), and transmission electron microscopy (4 cases). Positive immunoperoxidase staining for rabies was obtained in brain tissues from FA rabies-positive animals. All brain tissues from the 7 dogs stained by the immunoperoxidase method and the brain from the 1 dog stained by the FA method were negative for rabies. Rabies virus was not found in inclusion-containing neurons in the cases examined by transmission electron microscopy. These results emphasize the importance of FA testing and mouse inoculation for the diagnosis of rabies.  相似文献   

17.
Neurodegenerative processes are one of the main age-related features of dogs. Senile neurodegeneration can be clinically asymptomatic, “borderline” (i.e., a condition that is intermediate between normal and disease state) or progress toward overt clinical abnormalities, known as age-related cognitive disorders, cognitive dysfunction syndrome (CDS), or senile dementia. The aim of the present article is to review the rationale for the use of phosphatidylserine (PS), a natural phospholipid, in the management of brain neurodegenerative processes in senior dogs. The preliminary clinical data on PS supplementation in senior dogs will also be reviewed. There is evidence that PS is absorbed rapidly, reaches high concentrations in the brain, and is well tolerated. Phosphatidylserine has emerged to exert several in vitro and in vivo neuroprotective activities. It has been shown to positively affect neurotransmitter release and neurotransmitter receptor density in several brain regions from laboratory animals with memory impairments. Phosphatidylserine also was found to revert experimentally-induced amnesia in rats and improve memory deficits both in old animals and in elderly humans with various degrees of cognitive impairment and Alzheimer's dementia. On the basis of the data reported in the scientific literature, PS stands out as an essential “brain nutrient.” In view of these features, some supplements containing PS have been licensed recently as adjuvant treatment for canine and feline brain aging. The results of the studies on its use in the preventative and combined treatment of dogs with clinical features consistent with the diagnosis of CDS are reported. Although PS-based neuroprotection in dogs and cats is still at its infancy, the preliminary collected data look promising and thus merit further investigation.  相似文献   

18.
Changes in an individual's immune status are considered major contributing factors towards the morbidity of cancer and mortality of aging. To evaluate age-related changes in the immune status of dogs, the immunophenotypes (CD3, CD4, CD8 and CD21) of peripheral blood lymphocytes were measured in 160 healthy dogs aged from 1 to 17 years, and in 365 dogs with various tumors and at various stages. In healthy dogs, the absolute numbers of white blood cells, lymphocytes, and CD3(+), CD4(+) and CD21(+) lymphocytes decreased significantly with age. The relative percentages of lymphocytes and CD4(+) cells decreased significantly, while CD8(+) cells increased significantly with age. The CD4:CD8 ratio showed a significant age-related decrease. In contrast, dogs with tumors possessed significantly lower absolute numbers and relative percentages of all lymphocyte phenotypes, while the CD4:CD8 ratio was significantly higher than in age-matched controls. The relative percentages of CD3(+) and CD8(+) lymphocytes were significantly lower in dogs with distant metastases compared with dogs without metastases, and the CD4:CD8 ratio increased with advanced stage. These observations illustrate the significant changes in immune status with age and the presence of marked immunological defects in a large-scale study of dogs with advanced tumors.  相似文献   

19.
The primary study objective was to determine whether clinical examination and magnetic resonance imaging (MRI) can underestimate canine gliomatosis cerebri (GC); we also investigated immunohistochemical features. Seven dogs with GC were studied; four recruited specifically because of minimal MRI changes. Neuroanatomic localization and the distribution of MRI, gross and sub‐gross lesions were compared with the actual histological distribution of neoplastic cells. In six cases, clinical examination predicted focal disease and MRI demonstrated a single lesion or appeared normal. Neoplastic cells infiltrated many regions deemed normal by clinical examination and MRI, and were Olig2‐positive and glial fibrillary acid protein‐negative. Four dogs had concurrent gliomas. GC is a differential diagnosis for dogs with focal neurological deficits and a normal MRI or a focal MRI lesion. Canine GC is probably mainly oligodendrocytic. Type II GC, a solid glioma accompanying diffuse central nervous system neoplastic infiltration, occurs in dogs as in people.  相似文献   

20.
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