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1.
Acute Immobilization Stress and Intraventricular Injection of CRF Suppress Naloxone-Induced LH Release in Ovariectomized Estrogen-Primed Rats 总被引:1,自引:0,他引:1
Tatsuo Akema Atsuhiko Chiba Reiji Shinozaki Morihiro Oshida Fukuko Kimura & Jun-ichi Toyoda 《Journal of neuroendocrinology》1996,8(8):647-652
The present study was undertaken to evaluate the role and possible interaction of the endogenous opioid peptide (EOP) and corticotropin-releasing factor (CRF) in the acute stress-induced suppression of gonadotropin secretion in ovariectomized estrogen-primed rats. An intravenous (i.v.) injection of naloxone (10 or 20 mg/kg), an EOP antagonist, significantly elevated serum luteinizing hormone (LH) levels within 10 min in non-stressed animals. The naloxone-induced LH release was completely eliminated when tested 30 min after the onset of acute immobilization. In a subsequent study, it was found that suppression of the naloxone-induced LH release occurred as early as 5 min after the stress onset, and was still evident 60 min after the end of a 30-min period of immobilization. The effect of naloxone was restored 3 h after liberation of the animal from the 30-min immobilization. An intraventricular (i.c.v.) injection of CRF (1 or 5 μg) also significantly suppressed, in a dose-related manner, the effect of a subsequent i.v. injection of naloxone. However, an i.c.v. injection of α -helical CRF(9-41) (25 or 50 μg), a CRF antagonist, prior to immobilization, could not interfere with the suppressive effect of stress on naloxone-induced LH release. These results suggest that both acute immobilization stress and CRF can inhibit the LH secretory activity without mediation by EOP neurons. However, the stress-related suppression may involve non-CRF mechanism(s). 相似文献
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We experienced one necropsy case of brainstem encephalitis of Iizuka type (BSE) and one necropsy case of the brain-stem syndrome (BSS) of typical neuro-Beh?et's disease, and compared them clinically and neuropathologically. Clinically both of these cases showed chronic progressive mental disturbance, pseudobulbar paresis, spastic tetraparesis, cerebrospinal fluid pleocytosis, increased protein, and brainstem atrophy observed by X-CT. Neuropathologically, irregular, boundary-indistinct demyelinating lesions and obsolete softening lesions were sporadically found, associated with perivascular lymphocytic infiltration and gliosis centering on the brainstem. In this way, both cases were similar in many points except for the presence or absence of cutaneo-muco-ocular signs specific for Beh?et's disease. Also BSE and BSS reports in the literature showed that both diseases were similar not only in clinical findings consisting of mental disturbance and brainstem signs but also in neuropathological findings with similar topographical distribution of the same histopathological changes, including the variations and diversity of these characteristics. Especially of much interest is their similarity in characteristic mental disturbance. In discriminating BSE from multiple sclerosis and other diseases with exclusive involvement of the brainstem, it is important to understand their clinical characteristics. The characteristic mental disturbance includes damage to memory and sentiment, a change in personality, and lowering in spontaneity, but calculation ability and orientation are comparatively preserved. Of course the similarity in clinical and neuropathological findings does not necessarily mean the identical etiopathogenesis. However, it is possible to consider that neuro-Beh?et's disease (syndrome) may form a wide spectrum with BSE and typical neuro-Beh?et's disease at the both ends, regarding the time and spatial diversity of the appearance of cutaneo-muco-ocular signs. 相似文献
4.
Quantitative and qualitative changes of apolipoprotein AI-containing lipoproteins in patients on continuous ambulatory peritoneal dialysis 总被引:1,自引:0,他引:1
T Ohta S Hattori S Nishiyama A Higashi I Matsuda 《Metabolism: clinical and experimental》1989,38(9):843-849
Using immunoaffinity chromatography, two species of apo-AI containing lipoproteins (AILp); lipoprotein containing apo-AI and apo-AII (Lp-AI/AII), and lipoprotein containing apo-AI, but no apo-AII (Lp-AI) were isolated from 13 female patients on continuous ambulatory peritoneal dialysis (CAPD), then characterized. The results were compared with findings obtained in agematched normolipidemic (control I) and mild hypertriglyceridemic (control II) female subjects. In comparison with control I: In AILp, the levels of total cholesterol (TC), cholesteryl ester (CE) and phospholipid (PL), and the levels of apoE were significantly lower in the CAPD patients while the levels of triglyceride (TG) and apo-CIII were significantly higher in these patients. The levels of apo-AI and apo-AII did not differ between the CAPD and control subjects. In Lp-AI/AII, changes of TC, CE, PL, TG, and apolipoproteins were similar to those of AILp, except for the ratio of apo-AI/apo-AII and the level of apo-CII, which was higher in the CAPD patients. In Lp-AI, changes of TC, CE, PL, and TG were also similar to those of AILp and Lp-AI/AII, but the apo-AI level was significantly lower in the CAPD patients. In comparison with control II: In AILp, the levels of PL, apo-AI, apo-AII, and apo-E were significantly lower in CAPD patients, but the apo-CIII levels were significantly higher. In Lp-AI/AII, the levels of PL and apo-E were significantly lower in CAPD patients.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Two surgically cured cases of subependymoma with emphasis on magnetic resonance imaging 总被引:1,自引:0,他引:1
The authors describe two surgically cured cases of symptomatic subependymomas located in the lateral ventricle and septum pellucidum with emphasis on magnetic resonance imaging study. Both computed tomography and MRI revealed a calcified mass with repeated intratumoral hemorrhages. Cerebral angiograms disclosed rather hypovascular lesions. The histologic diagnosis was proven to be of subependymoma. The pertinent literature of surgically treated subependymomas is reviewed, and the characteristic biologic features are also discussed. 相似文献
6.
Toshihiko Imakiire Yuichi Kikuchi Muneharu Yamada Taketoshi Kushiyama Keishi Higashi Naomi Hyodo Kojiro Yamamoto Takashi Oda Shigenobu Suzuki Soichiro Miura 《Hypertension research》2007,30(7):635-642
The mechanisms of hypertensive nephrosclerosis are not fully understood. In experimental models of the disease, inflammatory reactions such as macrophage infiltration play an important role. In human hypertensive nephrosclerosis, however, there have been few studies examining the role of inflammation histologically. We investigated whether the number of infiltrating macrophages was increased in human hypertensive nephrosclerosis, and evaluated the effects of a blockade of the renin-angiotensin system on clinical and histological findings. We examined macrophage infiltration using immunohistochemistry in renal biopsy specimens obtained from 16 patients with hypertensive nephrosclerosis, 5 patients with IgA nephropathy, 5 patients with membranous nephropathy, and 5 patients with minimal change nephrotic syndrome. The number of infiltrating macrophages in glomeruli was significantly larger in the patients with hypertensive nephrosclerosis than in those with minimal change nephrotic syndrome. The patients with hypertensive nephrosclerosis were divided into groups based on their use of antihypertensive agents at the time of renal biopsy. We investigated the effects of antihypertensive agents on clinical findings, macrophage infiltration, and monocyte chemoattractant protein-1 expression. There was no difference in clinical findings between the hypertensive groups. The numbers of infiltrating macrophages and monocyte chemoattractant protein-1-positive cells in glomeruli were significantly smaller in patients treated with an angiotensin-converting enzyme inhibitor or angiotensin II type 1 receptor blocker, whereas calcium channel blockers had no influence on histological findings. In conclusion, inflammation is involved in the progression of human hypertensive nephrosclerosis and the inflammatory process is inhibited by blocking the renin-angiotensin system. 相似文献
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Enzymatic activities of NADH cytochrome c reductase and cytochrome c oxidase were determined in the mitochondria from various tissues of a patient with mitochondrial encephalomyopathy and compared with those of controls. NADH cytochrome c reductase in the present patient decreased significantly in the liver and spleen and to a less extent in the kidneys. On the other hand, cytochrome c oxidase of the patient decreased severely in the skeletal muscle and kidneys and partially in the heart. Difference spectrum of reduced-minus oxidized form of mitochondria from patient's skeletal muscle and heart showed a decrease of cytochrome aa3 peak in the alpha region at 605 nm. These results indicate that there are cryptic deficiencies in the segments of the respiratory chain in the mitochondria from several tissues of the present patient, such as liver, kidney, spleen without any clinical manifestation. The weakness and atrophy of skeletal muscle was, however, well correlated to the biochemical analysis. 相似文献
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N-Glycolylneuraminic acid (NeuGc) is distributed in most animals except humans and chickens. However, human and chicken cancerous tissues often synthesize this heterophilic sialic acid as a tumor-associated Hanganutziu-Deicher antigen [M. Naiki and H. Higashi, Adv. Exp. Med. Biol., 152: 445-456, 1982; H. Higashi et al., Cancer Res., 45: 3796-3802, 1985]. In this paper, NeuGc in human cancerous tissues and chicken Marek's disease lymphoma cell lines was determined quantitatively with gas chromatography-mass spectrometry analysis using mass fragmentography. The detectable limit of NeuGc was 40 pg (0.12 pmol) in each injection using 5 ng of trideuteriomethyl ester trideuteriomethyl glycoside of the sialic acid as an internal standard sample when a pair of ions at m/e 386 and 389 was chosen for ion monitoring. NeuGc was detected in ganglioside-rich fractions of various human cancerous tissues from 5 of 8 patients examined but was not detected in glycosphingolipids of normal human tissues. The contents of NeuGc in these cancerous tissues ranged from 0.02 to 0.5% of the total sialic acid content. NeuGc was also detected in freeze-dried samples of 5 different cell lines from chicken Marek's disease lymphomas but was not detected in a cell line from chicken lymphoid leukosis lymphoma and normal chicken skeletal muscle tissue. The contents of NeuGc in the positive cell lines ranged from 0.03 to 0.11% of the total sialic acid content. These results indicate that NeuGc can be synthesized in both humans and chickens in some cancers. 相似文献