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The effects of maternal ethanol exposure on neurotransmission and second messenger systems were examined in rats using histochemistry and in vitro autoradiography. Thirty % ethanol was administered to pregnant rats from gestational day 7 to the day of delivery. Quantitative autoradiography was used to map muscarinic cholinergic, dopamine D2, adenosine A1, and inositol 1,4,5-trisphosphate binding sites, as well as to localize adenylate cyclase and protein kinase C. We found no difference in the patterns of staining with acetylcholinesterase and Timm's stain between control and prenatally ethanol-exposed rats on postnatal day (PN) 30. In the ethanol-exposed rats, [3H]forskolin binding sites were increased during early development in the CA1 subfield of the hippocampus and the occipital cortex; [3H]phorbol ester binding sites were increased in the cortex, striatum, and hippocampus; hippocampal muscarinic cholinergic sites were increased on PN4 and 30; adenosine A1 binding was reduced on PN10 in most regions examined, but was increased in the CA1 subfield on PN30; dopamine D2 receptor levels were significantly reduced on PN30 in the striatum; and IP3 receptors were decreased in most regions studied, but particularly in the cerebellum. Thus, some of these changes were transient and others were long-lasting. Although histopathological abnormalities were minimal, the alterations of binding sites in the cerebellum (the coordination center) and in the hippocampus (related to memory and learning) that were detected may contribute to the behavioral and mental deterioration seen in the fetal alcohol syndrome.  相似文献   
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We encountered a rare case of hypersensitivity pneumonitis associated with bilateral hilar lymphadenopathy (BHL). The patient was a 53-year-old male, who developed dry cough and shortness of breath when using a humidifier since 1982. He was admitted to our hospital for further evaluation in 1987. Chest X-ray films showed BHL and ground glass appearance in the bilateral lung fields. Pulmonary function test indicated disturbance of diffusing capacity. Transbronchial lung biopsy revealed interstitial pneumonitis, and lymph node biopsy by mediastinoscopy showed lymphoid sinus histiocytosis without noncaseating granuloma. Provocation test using the humidifier was positive, and the diagnosis of humidifier lung with BHL was made.  相似文献   
5.
The role of intracellular Ca2+ in the degranulation of skinned mast cells   总被引:2,自引:0,他引:2  
K Tasaka  M Mio  M Okamoto 《Agents and actions》1987,20(3-4):157-160
The intracellular pH of rat peritoneal mast cells was slightly acidic and compound 48/80 induced a decrease in the cytoplasmic pH of these cells. By means of chemical skinning, it was revealed that perfusion with Ca2+ or inositol 1,4,5-trisphosphate (IP3) induced degranulation dose-dependently in mast cells at concentrations higher than 10 microM and 0.1 microM, respectively. Na+ was essential for the release of histamine from mast cells. An assay based on the binding of 45Ca to mast cell fragments revealed that the intracellular Ca store of the mast cell is located in the endoplasmic reticulum. IP3 liberated Ca from the endoplasmic reticulum.  相似文献   
6.
It is well known that long-term infection with Clonorchis sinensis often causes bile duct cancer, usually. It occurs in the intrahepatic bile duct. We encountered a rare case of clonorchiasis complicated with duodenal papillary cancer. The patient was a woman from China. Although clonorchiasis is rarely found in Japan, the promotion of international exchange may increase the number of visitors from endemic areas. Thus we must pay sufficient attention to this disease. Also, we reported that the microplate ELISA technique was useful in the diagnosis of clonorchiasis with high accuracy in this case.  相似文献   
7.
A Japanese woman with an 8-year history of lymphomatoid papulosis (LP) had lethal midline granuloma (LMG) develop at the age of 51 years. There were histologic similarities between LP and LMG seen in this patient. Surface phenotypic studies on nasal and cutaneous lesions demonstrated a population of T-cells expressing CD2, CD4, CD25, CD30, and histocompatibility antigen-DR (HLA-DR). Genotypic analyses of nasal and skin biopsy specimens disclosed a clonal rearrangement of the beta T-cell receptor gene with the same rearrangement pattern. These data indicate that this patient had LMG characterized by clonal peripheral T-cell lymphoma, which probably resulted from progression of the LP.  相似文献   
8.
The effect of chemical deafferentation, vagotomy(VGX), and gangliosympathectomy (GSX) on the density offibers containing calcitonin gene-related peptide (CGRP)and substance P (Sub.P) in the rat gastric wall was studied. Chemical deafferentation bycapsaicin abolished the density of CGRP-immunoreactive(IR) fibers, not Sub.P-IR fibers. Ten days after VGX,the density of CGRP-IR or Sub.P-IR fibers in the mucosa was largely reduced, while no reductionof CGRP-IR and Sub.P-IR fibers was seen in submucosaland muscular layers. GSX significantly reduced thedensity of CGRP-IR fibers in the mucosa and caused a moderate decrease in the fibers in submucosaland muscular layers. Pretreatment with6-hydroxydopamine, a neurotoxin for noradrenergicnerves, did not affect the density of CGRP-IR fibers inthe gastric wall. The density of Sub.P-IR fibers in thegastric wall was not affected by GSX. These studiesindicate that the CGRP-IR and Sub.P-IR fibers in themucosa are susceptible to extrinsic nerve denervation compared with those in the submucosa and musclelayers, that a major portion of the CGRP-IR fibers inthe mucosa is of both vagal and spinal origin, and thata major portion of the Sub.P-IR fibers in the mucosa is of vagal origin. Furthermore, thepresent results support that CGRP-IR fibers, notSub.P-IR fibers, in the rat stomach arecapsaicin-sensitive.  相似文献   
9.
Astemizole (0.5-5 mg/kg, p.o.) dose-dependently inhibited heterologous and homologous PCA reactions in rats at ID50 values of 1.48 mg/kg and 2.37 mg/kg, respectively. The inhibitory effect of astemizole on heterologous PCA was most remarkable when this compound was given p.o. 2 h prior to antigen challenge. Astemizole (0.1-5 mg/kg, p.o.) dose-dependently inhibited experimentally-induced asthma in guinea pigs at an ID50 of 0.86 mg/kg. Ex vivo, astemizole (0.5-5 mg/kg, p.o.) inhibited antigen-induced histamine release from lung pieces of sensitized guinea pigs. In in vitro experiments, the drug dose-dependently inhibited antigen-induced histamine and SRS-A releases from guinea pig lung pieces at concentrations of 0.05-10 microM. Furthermore, astemizole (0.1-10 microM) inhibited the histamine release induced by compound 48/80 and antigen-antibody reaction from rat peritoneal mast cells, and at 0.1-500 nM inhibited both leukotriene C4- and platelet-activating factor (PAF)-induced contraction of isolated guinea pig trachea at submicromolar concentrations. Astemizole not only inhibited 45Ca uptake into rat mast cells but also prevented the Ca2+ release from the intracellular Ca store induced by compound 48/80, although this compound did not affect the histamine release from permeabilized mast cells induced by Ca2+. Our results suggest that one of the antiallergic mechanisms of astemizole may be an inhibition of signal transduction from the mast cell membrane to the intracellular systems.  相似文献   
10.
H Koyama  K Nishimura  T Mio  A Ikeda  N Sugiura    T Izumi 《Thorax》1994,49(6):540-544
BACKGROUND--Diffuse panbronchiolitis (DPB) is characterised clinically by chronic airflow limitation and respiratory tract infection, and pathologically by chronic bronchiolar inflammation. To elucidate the functional differences between chronic obstructive pulmonary disease (COPD) and DPB the bronchial responsiveness to methacholine was compared in 64 patients with COPD and 32 patients with DPB, and the bronchodilator response was compared in 72 patients with COPD and 49 with DPB. METHODS--Bronchial responsiveness to methacholine was determined by the dosimeter method and expressed as PD20FEV1, and bronchodilator response was measured as the change in percentage predicted response with 5 mg nebulised salbutamol. RESULTS--Baseline FEV1 was similar in the two groups of patients. Patients with COPD were more responsive to methacholine than were those with DPB (geometric mean PD20FEV1 8.87 v 48.0 cumulative units). Reversibility of air flow obstruction, expressed as the difference between the percentage predicted postbronchodilator FEV1 and prebronchodilator FEV1, was significantly larger in patients with COPD than in those with DPB (7.87 (6.52)% v 4.16 (4.43)%). CONCLUSIONS--The observation that patients with DPB differ substantially in bronchial responsiveness from those with COPD is thought to reflect the difference in the mechanisms of these two diseases--that is, airway disease in DPB and more parenchymal disease in the group of patients with COPD. The nature of bronchiolar inflammation in COPD and DPB is also different, possibly explaining the difference in bronchial responsiveness. More fixed airflow limitation as a result of structural bronchiolar lesions in DPB will explain the smaller reversibility of airflow obstruction.  相似文献   
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