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2.
Neuropathology ; 21(3): 241-4, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11666023

RESUMO

Oculomotor paralysis of a patient with leukemia was revealed at autopsy to be caused by a hemorrhage in the oculomotor nerve. In a 63-year-old woman with pre-B-cell acute lymphatic leukemia, leukemic invasions occurred in her spinal cord and right oculomotor nerve during a hematological remission state. The oculomotor palsy was aggravated to complete paralysis during a leukemic relapse, which lasted until her death. An autopsy revealed a hemorrhage along with leukemic cells in the right oculomotor nerve at the segment in the upper orbital fissure. Although hemorrhagic oculomotor paralysis is a very rare complication, reports of its occurrence will likely increase with improved survival times of leukemia patients due to advances in chemotherapy.


Assuntos
Hemorragia/etiologia , Infiltração Leucêmica/complicações , Doenças do Nervo Oculomotor/etiologia , Nervo Oculomotor/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Medula Espinal/patologia , Doença Aguda , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Linfócitos B/metabolismo , Linfócitos B/patologia , Vértebras Cervicais , Feminino , Antígenos HLA/metabolismo , Hemorragia/patologia , Hemorragia/fisiopatologia , Humanos , Imuno-Histoquímica , Infiltração Leucêmica/patologia , Infiltração Leucêmica/fisiopatologia , Pessoa de Meia-Idade , Regressão Neoplásica Espontânea , Nervo Oculomotor/irrigação sanguínea , Nervo Oculomotor/fisiopatologia , Doenças do Nervo Oculomotor/patologia , Doenças do Nervo Oculomotor/fisiopatologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/fisiopatologia , Recidiva , Medula Espinal/irrigação sanguínea , Medula Espinal/fisiopatologia , Resultado do Tratamento
3.
Acta Neuropathol ; 102(1): 89-93, 2001 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-11547956

RESUMO

Respiratory insufficiency has been reported frequently in patients with myotonic dystrophy (MyD). Recent data support the hypothesis that this respiratory failure results from a primary dysfunction of the central nervous system. The medullary arcuate nucleus (ARC) has been shown to be involved in the regulation of respiration. We performed a quantitative study of neurons in the ARC in eight MyD patients, ten control subjects with other neurological diseases (control group A) and eight control subjects without neurological diseases (control group B). Alveolar hypoventilation of the central type occurred in three of the MyD patients but not in the remaining MyD patients or controls. The density of neurons in the ARC in MyD patients with hypoventilation was significantly lower than in MyD patients without hypoventilation and control groups A and B. There was no significant difference in the neuronal density of the ARC between MyD patients without hypoventilation and control groups A and B. These data suggest that the neuronal loss of the ARC is associated with the presence of hypoventilation in MyD.


Assuntos
Núcleo Arqueado do Hipotálamo/patologia , Distrofia Miotônica/patologia , Neurônios/patologia , Idoso , Contagem de Células , Feminino , Humanos , Hipoventilação/etiologia , Masculino , Bulbo , Pessoa de Meia-Idade , Distrofia Miotônica/complicações , Valores de Referência
4.
Rinsho Shinkeigaku ; 40(6): 600-4, 2000 Jun.
Artigo em Japonês | MEDLINE | ID: mdl-11086401

RESUMO

We report a case of NARP with a T-to-C point mutation at nt 8993 of mitochondrial DNA. A 37-year old man with mild mental retardation, retinitis pigmentosa, and clonic-tonic seizure was admitted to our hospital. The neurological examination revealed scanning speech, dystonic neck turning to the left side, and pyramidal tract signs. Serum-, CSF-lactate and pyruvate level were slightly elevated. Brain MRI findings showed cerebral atrophy, cerebellar cortical atrophy accompanied with dilation of forth ventricle, and high intensity lesions in the bilateral lenticular nuclei on T2 weighted images. Nucleotide sequence analysis of the mitochondrial DNA in the leukocytes demonstrated a T-to-C point mutation at nt 8993. To our knowledge, this is the first report of a Japanese patient with NARP associated with the T-to-C mutation at nt 8993 of mt DNA. Mitochondrial DNA analysis should be considered in the differential diagnosis of patients with retinitis pigmentosa and various neurological signs.


Assuntos
Ataxia/genética , DNA Mitocondrial/genética , Miopatias Mitocondriais/genética , Mutação Puntual , Retinose Pigmentar/genética , Adulto , Humanos , Masculino , Debilidade Muscular/genética , Síndrome
5.
Psychoneuroendocrinology ; 25(3): 277-87, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10737698

RESUMO

In order to investigate the possibility that i.p. injection of pentobarbital sodium (PB, 32 mg/kg bw) potentiates the GnRH pulse generator activity, effects of i.v. infusions of an opiate receptor antagonist naloxone (NAL, 2 mg/h) on the pulsatile LH secretion were compared in saline (SAL)- and PB-injected rats in proestrus and diestrus 1. In SAL-injected rats in proestrus, NAL infusions significantly increased both the frequency and amplitude of LH pulses, and also the overall mean LH concentration. In PB-injected rats in proestrus, all the parameters of the pulsatile LH secretion were similar to those in SAL-injected rats in proestrus. The NAL infusion in PB-injected rats caused an increase in the frequency, but it was similar to that in SAL-injected rats. But, increases in the amplitude and the overall mean LH observed during NAL infusions in PB-injected rats were greater than in SAL-injected rats. In SAL-injected rats in diestrus 1, NAL infusions increased all the parameters, as in rats in proestrus. In PB-injected rats in diestrus 1, LH secretion was severely suppressed. NAL infusions recovered the pulsatile LH secretion, but the frequency and the overall mean LH of the secretion were smaller than those obtained during NAL infusions in SAL-injected rats. In addition, characteristic increases in the MUA (volleys), which occur in association with the initiation of an LH pulse and thus are considered to represent an increased activity of the GnRH pulse generator, appeared more frequently during NAL infusions in PB-injected rats in proestrus than in SAL-injected rats. These results suggest that the GnRH pulse generator in rats in proestrus, but not in rats in diestrus 1, is refractory to PB and further is potentiated by PB in the response to NAL. Together with the fact that this dosage of PB blocks the surge of LH secretion in rats in proestrus, the concept of the existence of separate neuronal mechanisms responsible for the surge and pulsatile secretion of LH are supported.


Assuntos
Relógios Biológicos/efeitos dos fármacos , Hormônio Liberador de Gonadotropina/biossíntese , Neurônios/efeitos dos fármacos , Pentobarbital/farmacologia , Proestro/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Animais , Relógios Biológicos/fisiologia , Diestro/efeitos dos fármacos , Diestro/fisiologia , Eletrodos Implantados , Feminino , Hipotálamo/efeitos dos fármacos , Hipotálamo/metabolismo , Infusões Intravenosas , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Naloxona/administração & dosagem , Naloxona/farmacologia , Antagonistas de Entorpecentes/farmacologia , Neurônios/citologia , Neurônios/metabolismo , Periodicidade , Proestro/fisiologia , Ratos , Ratos Wistar
6.
Acta Neuropathol ; 99(3): 327-30, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10663978

RESUMO

The Ser149Arg mutation of peripheral myelin protein 22 (PMP22) was found in a 19-year-old woman with a sporadic case of Dejerine-Sottas disease. The patient showed delayed motor development. She walked for the first time with support at the age of 2 years. Scoliosis developed at age 4 years. Her walking ability was best at age 11. Thereafter, she showed progressive muscle weakness and sensory disturbances in the distal extremities. At the age of 18 years, the use of a wheelchair became necessary. Motor and sensory nerve conduction studies showed absent motor and sensory responses on electrical stimulation of the limb nerves. A sural nerve biopsy specimen showed marked decreases in the numbers of both large and small myelinated fibers, abundant onion-bulb formation, and hypomyelination. Electron microscopic observation revealed the presence of demyelinated axons and myelin sheaths disproportionately thin relative to axon diameter. That this was a de novo mutation was established by parentage testing and PMP22 gene analysis of the parents. The mutation seems to be novel and dominant.


Assuntos
Neuropatia Hereditária Motora e Sensorial/genética , Neuropatia Hereditária Motora e Sensorial/fisiopatologia , Proteínas da Mielina/genética , Nervos Periféricos/patologia , Nervos Periféricos/fisiopatologia , Adulto , Biópsia , Feminino , Neuropatia Hereditária Motora e Sensorial/patologia , Humanos , Microscopia Eletrônica , Nervos Periféricos/ultraestrutura , Nervo Sural/patologia , Nervo Sural/fisiopatologia , Nervo Sural/ultraestrutura
7.
J Biol Chem ; 275(5): 3335-42, 2000 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-10652322

RESUMO

This paper documents for the first time a volume-sensitive Ca(2+) influx pathway in osteocytes, which transmits loading-induced signals into bone formation. Stretch loading by swelling rat and chicken osteocytes in hypo-osmotic solution induced a rapid and progressive increase of cytosolic calcium concentration, [Ca(2+)](i). The influx of extracellular Ca(2+) explains the increased [Ca(2+)](i) that paralleled the increase in the mean cell volume. Gadolinium chloride (Gd(3+)), an inhibitor of stretch- activated cation channels, blocked the [Ca(2+)](i) increase caused by hypotonic solutions. Also, the expression of alpha1C subunit of voltage-operated L-type Ca(2+) channels (alpha1C) is required for the hypotonicity-induced [Ca(2+)](i) increase judging from the effect of alpha1C antisense oligodeoxynucleotides. Parathyroid hormone (PTH) specifically potentiated the hypotonicity-induced [Ca(2+)](i) increase in a dose-dependent manner through the activation of adenyl cyclase. The increases induced by both PTH and hypotonicity were observed primarily in the processes of the osteocytes. In cyclically stretched osteocytes on flexible-bottomed plates, PTH also synergistically elevated the insulin-like growth factor-1 mRNA level. Furthermore, Gd(3+) and alpha1C antisense significantly inhibited the stretch-induced insulin-like growth factor-1 mRNA elevation. The volume-sensitive calcium influx pathways of osteocytes represent a mechanism by which PTH potentiates mechanical responsiveness, an important aspect of bone formation.


Assuntos
Osso e Ossos/metabolismo , Cálcio/metabolismo , Hormônio Paratireóideo/metabolismo , Animais , Galinhas , Transporte de Íons , Osteoblastos/metabolismo , Osteoclastos/metabolismo , Ratos , Transdução de Sinais , Estresse Mecânico
8.
Artigo em Inglês | MEDLINE | ID: mdl-11464955

RESUMO

BACKGROUND: Abnormalities of hyaluronic acid (HA) of skin have been reported in patients with amyotrophic lateral sclerosis (ALS). However, little is known concerning the changes of serum HA in ALS. The purpose of this study was to investigate skin HA content and serum HA levels in ALS patients. METHODS: We measured skin HA content and serum HA levels in patients with ALS, and compared the results with those of control subjects. RESULTS: Skin HA content in ALS patients was significantly higher than in diseased control subjects and control subjects without neurological disorders, and increased significantly, the longer the duration of illness. Serum HA concentrations in patients with ALS were significantly higher than in diseased control subjects and in healthy control subjects, and were positively and significantly associated with duration of illness. There was an appreciable positive correlation between serum HA concentrations and skin HA content in ALS patients. CONCLUSION: These data suggest that a metabolic alteration of HA may take place in ALS and increased levels of serum HA may reflect an increased content of skin HA in ALS.


Assuntos
Esclerose Lateral Amiotrófica/sangue , Ácido Hialurônico/análise , Ácido Hialurônico/sangue , Pele/química , Adulto , Idoso , Esclerose Lateral Amiotrófica/patologia , Biópsia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pele/patologia
9.
Acta Neurol Scand ; 100(6): 377-84, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10589797

RESUMO

OBJECTIVES: Collagen abnormalities of skin have been reported in patients with amyotrophic lateral sclerosis (ALS). However, little is known concerning the aminoterminal propeptide of type III procollagen (PIIIP) and type III collagen in ALS. The aim of this study is to measure PIIIP, a precursor form of type III collagen, in skin and serum of ALS. MATERIAL AND METHODS: We studied PIIIP immunoreactivity of skin and measured serum levels of PIIIP in ALS patients, and the results were compared with those of control subjects. RESULTS: Collagen bundles in the dermis of ALS were immunohistochemically strongly positive for PIIIP as compared with those of controls. The optical density of PIIIP immunostaining reactivity in ALS patients was significantly higher than in controls, and was significantly increased with duration of illness. Serum PIIIP levels in patients with ALS were significantly increased as compared with those in diseased control subjects and those in healthy control ones, and were positively and significantly associated with duration of illness. There was an appreciable positive correlation between concentrations of serum PIIIP and the density of PIIIP immunoreactivity of skin in ALS patients. CONCLUSION: These data suggest that a metabolic alteration of PIIIP may take place in the skin of ALS and the increased levels of serum PIIIP may reflect the increased PIIIP immunoreactivity of skin in ALS.


Assuntos
Esclerose Lateral Amiotrófica/complicações , Esclerose Lateral Amiotrófica/metabolismo , Pró-Colágeno/metabolismo , Pele/patologia , Atividades Cotidianas , Adulto , Idoso , Esclerose Lateral Amiotrófica/sangue , Esclerose Lateral Amiotrófica/patologia , Biópsia , Estudos de Casos e Controles , Colágeno/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pró-Colágeno/sangue , Índice de Gravidade de Doença , Pele/metabolismo
11.
J Neurol Sci ; 167(2): 121-6, 1999 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10521551

RESUMO

Little is known concerning the changes of amino acid composition in different regions of the spinal cord in patients with amyotrophic lateral sclerosis (ALS). We performed quantitative amino acid analyses in the posterior funiculus, the lateral corticospinal tract, and the anterior horn of cervical enlargement of the spinal cord from seven ALS patients, and the results were compared with those of seven patients with other neurologic diseases (control A) and seven patients without neurologic diseases (control B). The levels of collagen-associated amino acids, hydroxyproline, proline, glycine, and hydroxylysine, were markedly lower in the lateral corticospinal tract and the anterior horn of ALS patients than in controls A and B. The contents of the acidic amino acids glutamate and aspartate were also significantly decreased in the lateral corticospinal tract and the anterior horn of ALS patients as compared with those of controls A and B. These data suggest that decreased contents of collagen-associated amino acids and excitatory amino acids are related to the degeneration of the upper and lower motor neurons in the spinal cord in ALS.


Assuntos
Aminoácidos/metabolismo , Esclerose Lateral Amiotrófica/metabolismo , Neurônios Motores/metabolismo , Medula Espinal/metabolismo , Adulto , Idoso , Esclerose Lateral Amiotrófica/patologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medula Espinal/patologia
12.
Acta Neurol Scand ; 100(2): 111-6, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10442453

RESUMO

OBJECTIVES: Type IV collagen (IV-C) abnormalities of skin and serum have been reported in patients with amyotrophic lateral sclerosis (ALS). However, there has been no study of urinary IV-C in ALS. The present study investigates urinary IV-C and the relation to its skin content in patients with ALS. MATERIAL AND METHODS: We studied IV-C immunoreactivity of skin and measured urinary levels of IV-C in ALS patients and controls. RESULTS: The basement membrane as well as blood vessels of skin in ALS patients was weakly positive for IV-C as compared with those of controls. Immunostaining became even weaker as ALS progressed. The urinary level of IV-C in ALS patients was significantly decreased as compared to diseased controls (P<0.001) and healthy controls (P<0.001), and was negatively and significantly associated with duration of symptoms (r=-0.85, P<0.001). There was an appreciable positive correlation between urinary IV-C levels and the density for IV-C immunoreactivity in ALS patients (r=0.84, P<0.01). CONCLUSION: These data suggest that a metabolic alteration of IV-C may occur in ALS patients and decreased levels of urinary IV-C may be related to the decreased IV-C immunoreactivity of skin in ALS.


Assuntos
Esclerose Lateral Amiotrófica/diagnóstico , Colágeno/urina , Idoso , Esclerose Lateral Amiotrófica/patologia , Esclerose Lateral Amiotrófica/urina , Biópsia , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Exame Neurológico , Valores de Referência , Pele/patologia
13.
Muscle Nerve ; 22(9): 1271-4, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10454725

RESUMO

Length of (CTG)n triplet repeats in myotonic dystrophy protein kinase gene (DMPK) was estimated in tumors, normal tissues of the same organs, muscles, and leukocytes from three myotonic dystrophy (DM) patients and a non-DM patient. Using cDNA 25 as a probe, a Southern blot analysis of EcoRI- and BglI-digested DNA from these tissues demonstrated the longest expansion of the repeats in the tumors of DM patients. In all tissues from a non-DM patient, the repeat length was confirmed to be stable by PCR analysis. Our data suggest that expanded (CTG)n repeat in tumor tissues may have increased the instability. This study emphasizes the importance of a long-term prospective study on the incidence of tumors in DM to clarify the pathological interrelation between the two entities.


Assuntos
Adenocarcinoma/genética , Neoplasias do Colo/genética , Insulinoma/genética , Distrofia Miotônica/complicações , Neoplasias Pancreáticas/genética , Proteínas Serina-Treonina Quinases/genética , Sequências Repetitivas de Ácido Nucleico , Neoplasias Gástricas/genética , Adenocarcinoma/complicações , Adenocarcinoma/enzimologia , Neoplasias do Colo/complicações , Neoplasias do Colo/enzimologia , DNA/química , DNA/metabolismo , Desoxirribonuclease EcoRI/metabolismo , Eletroforese em Gel de Campo Pulsado , Humanos , Insulinoma/complicações , Insulinoma/enzimologia , Leucócitos/enzimologia , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/enzimologia , Miotonina Proteína Quinase , Neoplasias Pancreáticas/complicações , Neoplasias Pancreáticas/enzimologia , Neoplasias Gástricas/complicações , Neoplasias Gástricas/enzimologia
14.
Intern Med ; 38(6): 504-6, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10411358

RESUMO

We describe a 51-year-old man with myotonic dystrophy (MyD) associated with insulinoma. In addition to the typical symptoms of MyD, he showed hypoglycemic attacks after meals. The radiological examination and selective blood sampling revealed an insulinoma in the head of the pancreas. The tumor was resected and histopathologically diagnosed as an insulinoma. In Southern blot analysis, CTG repeat of the myotonin protein kinase gene in the insulinoma showed the longest expansion, followed by normal tissue of the pancreas, muscle and white blood cells. Therefore, microsatellite instability was the most prominent in the tumor cells.


Assuntos
Insulinoma/complicações , Distrofia Miotônica/etiologia , Neoplasias Pancreáticas/complicações , Proteínas Serina-Treonina Quinases , Biomarcadores Tumorais/análise , Southern Blotting , Colangiopancreatografia Retrógrada Endoscópica , DNA de Neoplasias/análise , Humanos , Insulinoma/sangue , Insulinoma/diagnóstico , Insulinoma/cirurgia , Masculino , Pessoa de Meia-Idade , Distrofia Miotônica/sangue , Distrofia Miotônica/diagnóstico , Miotonina Proteína Quinase , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirurgia , Proteínas Quinases/genética , Tomografia Computadorizada por Raios X , Expansão das Repetições de Trinucleotídeos
15.
Neurology ; 51(4): 1121-4, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9781540

RESUMO

OBJECTIVE: To clarify the possible relation between the extent of involvement of catecholaminergic neurons and the presence of alveolar hypoventilation in patients with myotonic dystrophy (MyD). BACKGROUND: Respiratory insufficiency has been reported frequently in MyD patients. Recent data support the hypothesis that this respiratory failure results from a primary dysfunction of the CNS. METHODS: The authors performed a quantitative immunoreactive study of tyrosine hydroxylase immunoreactive (TH+) neurons linked to hypoventilation in the dorsal central medullary nucleus (DCMN), the ventral central medullary nucleus (VCMN), and the subtrigeminal medullary nucleus (SMN)--where the autonomic respiratory center is thought to be located--in eight MyD patients and in 10 age-matched control subjects. Alveolar hypoventilation of the central type was present in three of the MyD patients but not in the remaining MyD patients or the control subjects. RESULTS: The densities of TH+ neurons of the DCMN, the VCMN, and the SMN in MyD patients with hypoventilation were significantly lower than in those without hypoventilation (p < 0.02, p < 0.01, and p < 0.01, respectively) and control subjects (p < 0.01, p < 0.01, and p < 0.01, respectively). CONCLUSIONS: These data suggest that the loss of TH+ neurons of the DCMN, the VCMN, and the SMN is associated with the presence of hypoventilation in MyD and may be an important feature of MyD.


Assuntos
Catecolaminas/fisiologia , Distrofia Miotônica/patologia , Neurônios/citologia , Formação Reticular/patologia , Idoso , Contagem de Células , Feminino , Humanos , Masculino , Bulbo/patologia , Pessoa de Meia-Idade , Distrofia Miotônica/complicações , Neurônios/enzimologia , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/patologia , Tirosina 3-Mono-Oxigenase/análise
16.
Neurology ; 51(1): 114-20, 1998 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9674788

RESUMO

OBJECTIVE: To study type IV collagen of skin and serum in patients with ALS. BACKGROUND: Collagen abnormalities of skin have been reported in ALS patients. However, little is known concerning type IV collagen in ALS. METHODS: We studied type IV collagen immunoreactivity of skin and measured serum levels of the 7S fragment of the N-terminal domain of type IV collagen (7S collagen) in patients with ALS and control subjects. RESULTS: The basement membrane as well as blood vessels of skin in ALS patients was weakly positive for type IV collagen as compared with those of diseased control subjects. This weak immunostaining became more pronounced as ALS progressed. The optical density for type IV collagen immunoreactivity in ALS patients was significantly lower (p < 0.001) than in diseased control subjects and was significantly decreased with duration of illness (r = -0.85, p < 0.01). Serum 7S collagen levels in patients with ALS were significantly decreased (p < 0.01) as compared with those in diseased and healthy control subjects and were negatively and significantly associated with duration of illness (r = -0.81, p < 0.001). There was an appreciable positive correlation between concentrations of serum 7S collagen and the density for type IV collagen immunoreactivity in ALS patients (r = 0.81, p < 0.02). CONCLUSIONS: These data suggest that a metabolic alteration of type IV collagen may take place in the skin of ALS patients and that the decreased levels of serum 7S collagen may reflect a decreased type IV collagen immunoreactivity of skin in patients with ALS.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Colágeno/sangue , Pele/metabolismo , Idoso , Anticorpos , Membrana Basal/química , Membrana Basal/metabolismo , Colágeno/análise , Colágeno/imunologia , Feminino , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade , Pele/química
17.
Brain Res ; 784(1-2): 228-38, 1998 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-9518627

RESUMO

We investigated the distribution of neurons in the substantia nigra pars reticulata (SNr) which received cortical input. The activities of single SNr neurons were studied extracellulary in awake monkeys. SNr neurons showed excitatory and/or inhibitory responses to cortical stimulation. These responses were considered to be mediated by the subthalamic nucleus and striatum, respectively. The neurons receiving inhibitory input from the motor, premotor and supplementary motor areas (Motor-related cortical areas) were located in the lateral part of the SNr, whereas those with input from the medial, dorsal and orbital areas of the prefrontal cortex (PFmdo) were frequently found in the rostro-medial part of this nucleus. SNr neurons with inhibitory input from the ventral periprincipal area (PSv) were mainly distributed in the intermedio-lateral portion, with some degree of overlap with input from other cortical areas. The distribution of the excitatory input was almost similar to that of inhibitory one, but the excitatory input from the PSv was much stronger than that from the PFmdo. Some SNr neurons receiving cortical input were proved to project to the thalamus. Our results support the existence of several parallel organization of the cortico-basal ganglia loop circuits [G.E. Alexander, M.R. DeLong, P.L. Strick, Parallel organization of functionally segregated circuits linking basal ganglia and cortex, Ann. Rev. Neurosci., 9, 1986, pp. 357-381.], but interaction between the loops can not be ignored.


Assuntos
Córtex Motor/fisiologia , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Substância Negra/citologia , Animais , Núcleo Caudado/citologia , Núcleo Caudado/fisiologia , Estimulação Elétrica , Eletrofisiologia , Macaca , Córtex Motor/anatomia & histologia , Córtex Motor/citologia , Vias Neurais/anatomia & histologia , Vias Neurais/citologia , Vias Neurais/fisiologia , Córtex Pré-Frontal/anatomia & histologia , Córtex Pré-Frontal/citologia , Substância Negra/anatomia & histologia , Substância Negra/fisiologia , Tálamo/anatomia & histologia , Tálamo/citologia , Tálamo/fisiologia
18.
Neurology ; 50(2): 535-8, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9484393

RESUMO

Hypersomnia occurs frequently in patients with myotonic dystrophy (MyD). We performed a quantitative immunohistochemical study of serotonin (5-HT)-containing neurons linked to hypersomnia in the dorsal raphe nucleus (DRN) and the superior central nucleus (SCN) in 8 patients with MyD, 5 of whom showed hypersomnia, and in 12 age-matched controls. The densities of 5-HT neurons in the DRN and the SCN were significantly lower in MyD patients with hypersomnia than in MyD patients without hypersomnia and controls. These data suggest that the loss of 5-HT neurons of the DRN and the SCN is associated with the presence of hypersomnia in MyD.


Assuntos
Distúrbios do Sono por Sonolência Excessiva/etiologia , Distúrbios do Sono por Sonolência Excessiva/patologia , Distrofia Miotônica/complicações , Distrofia Miotônica/patologia , Neurônios/patologia , Núcleos da Rafe/patologia , Serotonina/análise , Idoso , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade
20.
Endocr J ; 45(4): 575-80, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9881909

RESUMO

To determine the effect of nicotine on LH and PRL secretion, nicotine bitartrate (nicotine) dissolved in saline was administered at 1400 h, just before the critical period for the preovulatory surge of LH and PRL secretion, either intracerebroventricularly (icv) or intravenously (iv) in female rats in proestrus. Nicotine neither at a dose of 5 microg nor at a dose of 10 microg injected icv at 1400 h caused significant changes in the surge of LH and PRL secretion. When nicotine was given iv at a dose of 100 microg, a significant decrease in LH and PRL concentrations occurred immediately, lasting for 2 h. After 1700 h, LH and PRL concentrations as high as that observed after 1700 h in saline-injected control rats were recovered, just as if nicotine caused a transient deficit of the surge secretion of these hormones. The results indicate that nicotine does not inhibit the preovulatory surge of LH and PRL secretion by acting at the hypothalamic level accessible via the third ventricle, but inhibits it by acting at certain other site(s).


Assuntos
Fase Folicular/metabolismo , Hormônio Luteinizante/metabolismo , Nicotina/farmacologia , Prolactina/metabolismo , Animais , Feminino , Fase Folicular/efeitos dos fármacos , Injeções Intraventriculares , Nicotina/administração & dosagem , Fluxo Pulsátil , Ratos , Ratos Wistar
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