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11.
The role of thromboxane A2 [TxA2] in liver injury in mice 总被引:1,自引:0,他引:1
The role of thromboxane A2 (TxA2) in CCl4-induced liver disease was investigated in mice. Significant elevation of TxB2 in the liver was observed 6 hours after the injection of CCl4. Administration of OKY-046, a selective TxA2 synthetase inhibitor (10 and 50 mg/kg) and ONO-3708, a TxA2 receptor antagonist, (0.5, 1 and 2 mg/Kg) suppressed the elevation of serum GOT and GPT levels and histopathological changes of the liver. In addition, OKY-046 inhibited the elevation of TxB2 in the liver. When U-46619, a stable TxA2 mimetic was injected i.v. into the mice, clear elevation of serum GOT and GPT levels and histopathological score of the liver were observed. These results suggest that TxA2 play a role for the onset of CCl4-induced liver injury in mice. 相似文献
12.
Conformational change of bovine serum albumin by heat treatment 总被引:1,自引:0,他引:1
Kunio Takeda Akira Wada Kazuo Yamamoto Yoshiko Moriyama Koichiro Aoki 《Journal of Protein Chemistry》1989,8(5):653-659
The thermal denaturation of bovine serum albumin (BSA) was studied at pH 2.8 and 7.0 in the range of 2–65°C. The relative proportions of -helix, -structure, and disordered structure in the protein conformation were determined as a function of temperature, by the curve-fitting method of circular dichroism spectra. With the rise of temperature at pH 7.0, the proportion of -helix decreased above 30°C and those of -structure and disordered structure increased in the same temperature range. The structural change was reversible in the temperature range below 45°C. However, the structural change was partially reversible upon cooling to room temperature subsequent to heating at 65°C. On the other hand, the structural change of BSA at pH 2.3 was completely reversible in the temperature range of 2–65°C, probably because the interactions between domains and between subdomains might disappear due to the acid expansion. The secondary structure of disulfide bridges-cleaved BSA remained unchanged during the heat treatment up to 65°C at pH 2.8 and 7.0. 相似文献
13.
A biphasic excitability change in hindlimb motoneurons evoked by stimulation of the nucleus raphes magnus in the cat 总被引:1,自引:0,他引:1
M Edamura M Aoki 《Comparative biochemistry and physiology. A, Comparative physiology》1989,93(4):711-716
1. The influence of electrical stimulation of the nucleus raphes magnus (RM) on spinal segmental systems were examined. 2. RM stimulation produced an initial increase and a subsequent suppression of the amplitude of both fiextor and extensor lumbar monosynaptic reflex potentials (MSRs). 3. Intracellular recordings were made from alpha-motoneurons of the common peroneal nerve (flexor) and the tibial nerve (extensor). RM stimulation evoked postsynaptic potentials with a time course similar to that of MSR facilitation. 4. RM stimulation inhibited the aggregate excitatory synaptic potential (EPSP) evoked by stimulation of group I afferent fibers without apparent changes in the motoneuronal membrane potential. 5. These data suggest that the RM-evoked biphasic effect on MSR consists of early facilitation due to EPSP, and late inhibition possibly due to presynaptic inhibition of group I afferent fibers. 相似文献
14.
Differences in lectin binding patterns of normal human endometrium between proliferative and secretory phases 总被引:3,自引:0,他引:3
Lectin binding patterns in normal human endometrium were examined by light and electron microscopy using seven different lectins (ConA, WGA, RCA, PNA, UEA-1, DBA, and SBA). For light microscopic observations, criteria based on the incidence and intensity of cells positive for the lectin staining were adopted to evaluate the different staining patterns of the proliferative and secretory endometria obtained by the avidin-biotin-peroxidase complex (ABC) technique. At the light microscopic level, ConA, WGA, and RCA stained endometrial glandular cells in both phases. The number of PNA-positive cells with the binding sites entirely limited to the apical surface tended to be reduced slightly in the secretory phase. UEA-1 weakly stained the apical surface of glandular cells in the proliferative phase but not in the secretory phase. Among the lectins used in this study, DBA and SBA displayed remarkable changes between the phases. That is, in the proliferative phase they produced only a faint or slight positive stain at the apical surface, but the incidence and intensity of DBA- and the SBA-positive glandular cells increased in the secretory phase. By electron microscopy, the reaction product of ConA was observed in the plasma membrane, endoplasmic reticulum, nuclear envelope, and the Golgi apparatus, and the binding sites of RCA and DBA were observed in the plasma and Golgi membranes. Between both phases, the reactivity of ConA and RCA showed almost no change. However, the secretory endometrial cells containing the DBA-positive Golgi apparatus were markedly increased in number compared with the proliferative ones bearing the lectin-positive organelles.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
15.
Scale Arrangement Pattern in a Lepidopteran Wing. 1. Periodic Cellular Pattern in the Pupal Wing of Pieris rapae 总被引:1,自引:1,他引:0
In most species of lepidopteran insects, anteroposterior rows formed by scales are arranged at regular intervals in the adult wing; within each row two kinds of scales are alternately arranged. To investigate the cellular basis for the scale arrangement pattern, we examined cell arrangement in the epidermal monolayer of the pupal wing of a small white cabbage butterfly, Pieris rapae , by scanning electron microscopy and light microscopy.
The arrangement of scale precursor cells, closely resembling that of scales in the adult wing, was observed in the wing epidermis of the early pupa. Scale precursor cells are proximodistally elongated and form anteroposterior rows. Within a row two kinds of scale precursor cells are nearly alternately arranged, which is not so precise as the alternation of scales in the adult wing. Individual rows of scale precursor cells are separated by rows of single or double undifferentiated general epidermal cells. Occasionally, arrangement abnormalities occur both in the adult and the pupal wing. The cellular basis for the regular spacing of scale rows is discussed. 相似文献
The arrangement of scale precursor cells, closely resembling that of scales in the adult wing, was observed in the wing epidermis of the early pupa. Scale precursor cells are proximodistally elongated and form anteroposterior rows. Within a row two kinds of scale precursor cells are nearly alternately arranged, which is not so precise as the alternation of scales in the adult wing. Individual rows of scale precursor cells are separated by rows of single or double undifferentiated general epidermal cells. Occasionally, arrangement abnormalities occur both in the adult and the pupal wing. The cellular basis for the regular spacing of scale rows is discussed. 相似文献
16.
M Kato H Nakayama Z Makita S Aoki Y Kuroda K Misawa H Yoshida K Yanagisawa S Nakagawa 《Hormones et métabolisme》1989,21(5):245-248
We have developed a radioimmunoassay (RIA) for nonenzymatically glycated serum proteins. The polyclonal antibodies prepared against reduced glycated human albumin were specific for the glucitollysine residues of serum proteins. Serum proteins from diabetic patients (n = 25) contained 5.3 +/- 2.8 nmoles of glucitollysine/mg protein, compared to 2.0 +/- 0.2 in controls (n = 20). The intra- and inter-assay variables were 3.2-6.2% and 4.4-8.6%, respectively. Results from this assay procedure correlated well with those from the boronate affinity chromatography procedure (r = 0.94; P less than 0.001). The data suggested that diabetic serum proteins contained at least 2.5 times as much immunochemically detectable glucitollysine residures as normal serum proteins after reduction of the proteins with sodium borohydride. 相似文献
17.
Immunocytochemical studies on the pituitary pars distalis of the Japanese long-fingered bat,Miniopterus schreibersii fuliginosus 总被引:1,自引:0,他引:1
Professor Shin-ichi Mikami Shin Chiba Hitoshi Hojo Kazuyuki Taniguchi Kaoru Kubokawa Susumu Ishii 《Cell and tissue research》1988,251(2):291-299
Summary Immunocytochemical studies were performed to describe the characteristics of cell types and their distribution in the pars distalis of Japanese long-fingered bat, Miniopterus schreibersii fuliginosus, collected at various stages of the reproductive cycle. Six distinct cell types have been identified in the pars distalis by the unlabeled immunoperoxidase technique and by the ABC method. Growth hormone (GH) and prolactin (PRL) cells were immunostained with antisera against chicken GH and ovine PRL. The GH-immunoreactive cells were round or oval orangeophilic cells distributed throughout the pars distalis with prominent aggregation in the posterolateral region. The PRL cells were pleomorphic carminophilic cells that occurred in small groups within the central and dorsocaudal regions of the pars distalis. They were sparsely distributed in the central region of the pars distalis in the hibernating bats, but increased significantly in the pregnant and lactating bats. The adrenocorticotropic (ACTH) cells were large round or polygonal amphophilic cells in the rostroventral and ventrolateral regions of the pars distalis. The thyrotropic (TSH) cells were small rounded or polygonal and distributed mainly in the ventrolateral region of the pars distalis. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) cells were identified immunocytochemically with antisera against the specific beta subunits of ovine LH and rat FSH. There were two populations of LH and FSH cells, one aggregated in the zona tuberalis and the other scattered singly throughout the rest of the pars distalis. The aggregated cells were immunoreactive with both antisera directed to LH and FSH, while scattered cells were reactive solely with antiserum to either LH or FSH and exhibited seasonal variations. In females, the proportional volume of the pars distalis occupied by LH cells was significantly reduced during pregnancy and lactation. No evidence of involution was observed in pars distalis cells except for PRL cells in males or females during hibernation. 相似文献
18.
T. Aoki K. Nobuta the late Y. Nishikawa H. Shimma 《Zeitschrift fur angewandte Ichthyologie》1988,4(4):174-177
Common DNA fragments of the α-globin gene were observed in five races of adult common carp: mirror, scaly-German, Yamato-Suwa, Yamato-Saku, and Yamato-hybrid carp. There were different hybridization patterns between the Japanese carp and the German carp. Three to four DNA fragments hybridized with α-globin and indicated polymorphysim in the globin gene of carp.
DNA-Homologie des α-Globin-Genes bei fünf Karpfenrassen, Cyprinus carpio
Identische Fragmente des α-Globin-Genes wurden bei fünf Rassen des adulten gemeinen Karpfens (Spiegeikarpfen, deutscher Schuppenkarpfen, Yamato-Suwa-, Yamato-Saku-und Yamato-Hybrid-karpfen) gefunden. Es gab verschiedene Hybridisationsmuster zwischen dem japanischen und dem deutschen Karpfen. Drei bis vier DNA-Fragmente hybridisierten mit α-Globin und wiesen auf einen Polymorphismus des Globingenes des Karpfens hin.
Homologie de DNA dans le gène d'α-globine chez cinq races de carpe, Cyprinus carpio
Des fragments communs de DNA dans des gènes d'α-globine ont été observés chez cinq races de carpe commune adulte: carpe miroir, allemande écailleuse, Yamato-Suwa, Yamato-Saku et Yamato-hybride. Il existait différentes combinaisons d'hybridation entre la carpe allemande et la carpe japonaise. Trois à quatre fragments de DNA hybridisaient avec l'α-globine et indiquaient un polymorphisme dans les gènes de globine de carpe. 相似文献
Zusammenfassung
DNA-Homologie des α-Globin-Genes bei fünf Karpfenrassen, Cyprinus carpio
Identische Fragmente des α-Globin-Genes wurden bei fünf Rassen des adulten gemeinen Karpfens (Spiegeikarpfen, deutscher Schuppenkarpfen, Yamato-Suwa-, Yamato-Saku-und Yamato-Hybrid-karpfen) gefunden. Es gab verschiedene Hybridisationsmuster zwischen dem japanischen und dem deutschen Karpfen. Drei bis vier DNA-Fragmente hybridisierten mit α-Globin und wiesen auf einen Polymorphismus des Globingenes des Karpfens hin.
Résumé
Homologie de DNA dans le gène d'α-globine chez cinq races de carpe, Cyprinus carpio
Des fragments communs de DNA dans des gènes d'α-globine ont été observés chez cinq races de carpe commune adulte: carpe miroir, allemande écailleuse, Yamato-Suwa, Yamato-Saku et Yamato-hybride. Il existait différentes combinaisons d'hybridation entre la carpe allemande et la carpe japonaise. Trois à quatre fragments de DNA hybridisaient avec l'α-globine et indiquaient un polymorphisme dans les gènes de globine de carpe. 相似文献
19.
The possibility of involvement of calcium ions in the hatching of Schistosoma mansoni eggs in water is described. The hatching of S. mansoni eggs under low osmotic pressure was partially inhibited by EGTA (5 mM), lanthanum chloride (1-5 mM), and ruthenium red (0.1-1 mM). The reagents used in these experiments were not toxic to the eggs however, because miracidia hatched normally when the reagents were removed. 相似文献
20.
Anti-shock effects of human superoxide dismutase in splanchnic artery occlusion (SAO) shock 总被引:2,自引:0,他引:2
H Bitterman N Aoki A M Lefer 《Proceedings of the Society for Experimental Biology and Medicine. Society for Experimental Biology and Medicine (New York, N.Y.)》1988,188(3):265-271
We studied the effects of human superoxide dismutase (h-SOD) in splanchnic artery occlusion (SAO) shock. Pentobarbital anesthetized rats subjected to total occlusion of the superior mesenteric and the celiac arteries for 40 min developed a severe shock state usually resulting in a fatal outcome within 20 min after the release of the occlusion. h-SOD (10 mg/kg) was infused intravenously starting at reperfusion and lasting for 10 min. SAO shock rats treated with h-SOD maintained postreperfusion MABP at significantly higher values compared to rats receiving the vehicle (final MABP 84 +/- 6 vs 46 +/- 1 mm Hg, P less than 0.01, respectively). Treatment with h-SOD attenuated the plasma accumulation of free amino-nitrogen compounds (P less than 0.01 from vehicle) as well as the activity of the lysosomal protease cathepsin D (P less than 0.05 from vehicle). Furthermore, the plasma activity of a myocardial depressant factor was significantly lower in h-SOD-treated rats than in SAO rats receiving only the vehicle (27 +/- 1 vs 64 +/- 3 U/ml, P less than 0.01). SAO shock rats treated with h-SOD also exhibited a significantly higher survival rate than the SAO shock +/- vehicle group (88% vs 11%, P less than 0.01, respectively). These results support the role of oxygen-derived radicals in the pathophysiology of SAO shock, and indicate that h-SOD effectively ameliorates the deleterious effects of oxygen radicals in this severe model of ischemia and reperfusion. 相似文献