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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
14.
Although the human tumor clonogenic assay (HTCA) is extremely reliable in determining clinical correlations, it is a complicated process requiring considerable time in order to obtain results. Thus, an experimental study on cytopathologic observation (cytologic assay) and comparative evaluation between it and HTCA were performed in order to establish a more rapid and accurate drug sensitivity test. Materials included Colon 26, a cell line established in our department, malignant effusion and surgical specimens. In carrying out HTCA according to the Hamburger-Salmon method, the cell suspension samples following exposure to anti-tumor agents (MMC, L-PAM, ADM, CDDP) were cultivated in test tubes for 3-8 hours and stained by the Papanicolaou and Giemsa methods. According to Tokita's criteria, when cellular changes showed as nuclear pyknosis and nuclear destruction were found to have increased significantly in comparison with a control group, the cells were judged to be sensitive. Very similar and parallel results were obtained between HTCA and cytologic assay in this study, with a significant correlation. Cytologic assay was proved to be an easy, rapid and accurate method for testing drug sensitivity and its clinical application can be expected in the future. 相似文献
15.
H Nakagawa M Kikuhara M Sato K Sakai S Kimura 《Gan to kagaku ryoho. Cancer & chemotherapy》1987,14(9):2767-2770
A 50-year-old woman with bilateral inflammatory breast cancer (T4, N1b, M1, Stage IV) underwent right extended radical mastectomy and left modified radical mastectomy following pre-operative administration of carcinostatics (ADM, 5-FU) and irradiation. However, tumor recurrence was observed at the skin and right pleural cavity after the operation. Adriamycin-containing combination chemotherapy and radiation therapy were performed, but no significant response was obtained. CDDP was then administered intravenously at a daily dose of 62.5 mg/m2 at intervals of 60 days. The pleural effusion disappeared and the extent of skin metastasis was reduced, resulting in partial response which lasted for 90 days. The serum CEA level decreased from 13.1 ng/ml to 2.3 ng/ml. As the side effects of this therapy, slight nausea, vomiting and general fatigue were observed. This result suggested that CDDP is an effective drug for inflammatory breast cancer. 相似文献
16.
The authors studied the clinical features and outcome at 6 months in 191 patients with subarachnoid hemorrhage (SAH) from ruptured aneurysms. Aneurysm repair (AR) was undertaken in 123 cases (64.4%). In the non-AR group (n = 68), 48.5% of the patients were 70 years of age or older, compared with 12.2% in the AR group. The duration from onset to admission was less than 3 hours in 48 non-AR cases (70.6%) and in 42 AR cases (34.1%). Among non-AR patients, 63.2% were Hunt and Hess grade IV or V, whereas the figure for AR patients was only 14.7%. By 6 months after SAH, 94.1% of non-AR patients had died, and the remainder were vegetative or severely disabled. In contrast, only 15.4% in the AR group died, and over 50% showed good recovery. The large majority of non-AR patients were treated conservatively because they were judged to be poor surgical risks and, among these patients, nearly one half were elderly. In the 10 elderly patients considered good surgical candidates, vasospasm was the most common reason (70%) for not performing AR. 相似文献
17.
Thyroid function tests were studied in 105 severely disabled children. Fifty-four cases (53%) showed following abnormalities. Serum TSH concentration was increased in 2 cases. Both serum T4 and T3 levels were decreased in 18 cases (17%). Only the serum T4 level was decreased in 25 cases (24%). Only the serum T3 level was decreased in 10 cases (9.5%). Two patients showed primary hypothyroidism. Two patients (monozygotic twins) were suspected to have subclinical hypothalamic-pituitary hypothyroidism caused by septo-optic-dysplasia. Abnormal thyroid functions were caused by anticonvulsants in most patients. The serum T4 level was correlated with the number of anticonvulsants, but not correlated with motor performance (daily activity) or feeding function. Four patients who had low T4 level or low T4 and T3 levels were received L-thyroxine supplementation, but no clinical improvement was observed. The serum TSH concentration was decreased and the TRH test showed hyporeaction in all of these cases. The low T3 level and normal T4 level were not related to anticonvulsant administration. Two of these patients were in poor nutritional condition, resulting in so called low T3 syndrome. 相似文献
18.
Liver histopathology in clinical Reye syndrome 总被引:1,自引:0,他引:1
Analysis of the liver histopathology in 19 children with clinical Reye syndrome (RS) revealed that nine had diffuse panlobular steatosis, one giant cell hepatitis, one a mild choledochal cyst with inflammation, two multifocal spotty necrosis and one multiple centrilobular necrosis, the other five being normal. Four of the nine patients with diffuse panlobular steatosis showed microvesicular fatty droplets with central nuclei, which was consistent with findings characteristic for typical RS. Two cases showed a periportal area dominant macrovesicular fatty change, which was highly suggestive for metabolic disorder. In the other three cases, the findings were so variable in terms of the size of lipid droplets and the location of nuclei in hepatocytes that it was not possible to provide any clue for defining a diagnosis. These results confirmed the legitimacy of the diagnostic criteria of RS which included a liver biopsy as one of the mandatory conditions. They also indicated that RS-mimicking clinical pictures can be presented by miscellaneous conditions in which liver histology does not necessarily helpful in establishing definite diagnosis. 相似文献
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A Miura Y Ukai T Matsuzaki N Taniguchi S Hayashi S Kano Y Kimura K Kimura H Enomoto 《Arzneimittel-Forschung》1986,36(9):1323-1328
The effects of methyl 2,6-dimethyl-4-(2-nitrophenyl)-5-(2-oxo-1,3,2-dioxaphosphorinan-2- yl)-1,4- dihydropyridine 3-carboxylate (DHP-218), a new dihydropyridine calcium antagonist, on vascular smooth muscles, cardiac muscles and [3H]-nitrendipine binding to the cardiac muscle and brain membranes were investigated in vitro. Vascular smooth muscles: Calcium-induced contraction of the rat aorta in high K+ solution was inhibited by DHP-218 with the pA2 value of 9.11. The IC50 value for the inhibitory effects of this compound in high K+-induced and phenylephrine-induced contraction was 6.3 nmol/l and 66 nmol/l, respectively. Vasodilatory effects of this drug on various blood vessels of rabbits contracted by high K+ appeared to a similar extent. The onset of the vasodilatory effect was very slow and the recovery rate of vasodilatory response after washout with the bathing solution containing high K+ or phenylephrine was also very slow. Cardiac muscles: Negative chronotropic and inotropic actions were observed at concentrations more than 30 and 100 nmol/l, respectively. Duration of the plateau phase of normal action potential was shortened and the amplitude and duration of slow action potential were reduced at concentrations more than 1 mumol/l. Very high vasculoselectivity was observed. Displacement of [3H]-nitrendipine binding: The pattern of displacement of [3H]-nitrendipine binding by DHP-218 was very similar to that of other 1,4-dihydropyridines but this compound was about 70 times less potent than nifedipine in [3H]-nitrendipine displacement capacity. These results indicate that DHP-218 has specific vasodilatory action due to calcium antagonism, but association and dissociation rates with tissue and receptors were different from those of nifedipine. 相似文献