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31.
This experiment was designed to evaluate effects of RA642, a pyrimido-pyrimidine derivative, on renal nerve activity (RNA), mean blood pressure (MBP), central venous pressure (CVP), and heart rate (HR) during hemorrhagic shock in anesthetized rabbits. Hemorrhagic hypotension of 30 mmHg was induced by rapid bleeding and was controlled by a servocontrolled pump. Following the onset of hemorrhagic hypotension, RNA response showed a triphagic pattern: an initial increase in RNA and a secondary increase followed by a profound decline in RNA. In all animals, decreases in RNA occurred within approximately 30 min after bleeding in association with significant decreases in heart rate. When RNA fell to near noise level, the effects of RA642 (0.25 mg/kg, iv, N = 10), physiological saline (N = 7), epinephrine (10 micrograms/kg, iv, N = 6), and dopamine (10 micrograms/kg, iv, N = 5) were then tested. Intravenous injection of saline produced no significant improvements of hypotension nor of reduction in RNA. However, treatment with RA642 produced a significant increase in MBP simultaneously with an increase in RNA. During the hypovolemic hypotensive phase, tachycardia did not occur after the treatment with RA642. Twenty-five minutes after the retransfusion, MBP and RNA in the RA642-treated group were at significantly higher levels than in the saline group. HR did not significantly change with the RA642 treatment after the retransfusion. In another six animals, when RNA fell to near noise level, epinephrine caused a transient increase in MBP and HR. Ventricular arrythmias occurred in 50% of epinephrine-treated animals. However, the level of MBP as improved by epinephrine was significantly lower than that by RA642 at 25 min after the retransfusion.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
32.
33.
M Kusunoki Y Shoji Y Sakanoue H Yanagi S Fujita T Yamamura J Utsunomiya 《The Journal of surgical research》1991,51(4):293-296
The effect of gamma-aminobutyric acid (GABA) on the human internal anal sphincter was investigated. Cumulative applications of GABA produced concentration-dependent contractions (10(-8)-10(-5) M) of the isolated human sphincter. Pretreatment with bicuculline (GABAA antagonist) turned them to relaxation. Muscimol, a GABAA agonist, induced concentration-dependent contractions (10(-8)-10(-5) M); however, baclofen (GABAB agonist, 10(-8)-10(-5) M) promoted concentration-dependent relaxation of the strips. These results suggested that both excitatory GABAA receptors and inhibitory GABAB receptors exist in the internal anal sphincter. Oral administration of sodium valproate (1600 mg/day), a GABA transaminase inhibitor, enhanced the anal canal resting pressure in 10 normal volunteers. Anal manometry showed a significant elevation in tonus without affecting amplitudes or frequencies. These results indicated that endogenous GABA, which was increased by sodium valproate, produced elevations in the anal canal resting pressure through its specific receptors in the human internal anal sphincter. 相似文献
34.
35.
Plasma volume estimation using indocyanine green with biexponential regression analysis of the decay curves 总被引:2,自引:0,他引:2
We studied seven analytical methods of estimating the plasma volume from the decay curves of indocyanine green. Fifteen volunteers received 1.0 mgkg−1 of the dye by intravenous injection and the plasma concentration was measured continuously using spectrophotometry. Plasma volumes were calculated using three single-regression methods (1-a, 1-b, 1-c) and four biexponential regression methods (2-a, 2-b, 2-c, 2-d). The means (SD) of 1-a, 1-b and 1-c were 39 (5.0), 44 (5.7) and 54 (11.5) mlkg−1 , respectively, and these were significantly different from each other (p < 0.05). The values for methods 2-b, 2-c and 2-d were similar to each other: 39 (4.6), 40 (4.1) and 40 (4.0) mlkg−1 , respectively. These required more than 3 min circulation or mixing time. When the time allowed for mixing was less than 3 min (method 2-a) the plasma volume was underestimated. We conclude that plasma volume estimation using indocyanine green and spectrophotometry is most accurate when the mixing time is adequate (3–5 min) and the decay curves are analysed using biexponential regression. 相似文献
36.
Cadherin dysfunction in a human cancer cell line: possible involvement of loss of alpha-catenin expression in reduced cell-cell adhesiveness. 总被引:37,自引:0,他引:37
Y Shimoyama A Nagafuchi S Fujita M Gotoh M Takeichi S Tsukita S Hirohashi 《Cancer research》1992,52(20):5770-5774
A human lung cancer cell line, PC 9, was analyzed to elucidate the molecular mechanisms of dysfunction of cadherin-mediated cell-cell adhesion in cancer. Although PC 9 cells strongly expressed E-cadherin at the cell membrane, which was indistinguishable immunochemically from functional E-cadherin, they did not show tight cell-cell adhesion and had reduced E-cadherin-mediated aggregation activity. Immunoprecipitation with E-cadherin and Western blot analysis revealed that PC 9 cells did not express alpha-catenin, a cadherin-associated protein, suggesting that this was the cause of the cadherin dysfunction in the cell line. In addition, Northern and Southern blot analyses disclosed homozygous deletion of part of the alpha-catenin gene, which might have resulted in the loss of alpha-catenin expression in PC 9 cells. 相似文献
37.
X Renming K Ishihara M Sasa H Ujihara T Momiyama Y Fujita N Todo T Serikawa J Yamada S Takaori 《European journal of pharmacology》1992,223(2-3):185-192
The effects of CNK-602A (N-[(6-methyl-5-oxo-3-thiomorpholinyl) carbonyl]-L-histidyl-L-prolinamide), a novel thyrotropin-releasing hormone related analog, were investigated on absence-like seizure and tonic convulsion in the spontaneously epileptic rat (SER), which is a genetically defined double-mutant. When CNK-602A of 0.2-1 mg/kg was given intravenously to the animal, there were no changes in the background EEG except for an increase in low-voltage fast waves concomitant with behavioral alertness. However, CNK-602A suppressed absence-like seizure and tonic convulsion in a dose-dependent manner for over 1 h. These antiepileptic effects of CNK-602A on both seizures were antagonized by pretreatment with haloperidol (1 mg/kg, i.p.). It was found, using a brain in vivo microdialysis method, that CNK-602A at a dose of 1 mg/kg, which inhibits the seizures, increased the release of dopamine in the caudate nucleus. These results suggest that CNK-602A inhibits the seizures of SER in a similar manner to thyrotropin-releasing hormone (TRH), probably by increasing the release of dopamine in the central nervous system. In addition, the antiepileptic effects of CNK-602A were more potent and lasted longer than those of TRH. 相似文献
38.
Takuo Fujita Masaaki Fukase Takao Shimada Hironosuke Yamamoto 《Journal of bone and mineral metabolism》1992,10(1):37-40
In addition to estrogen widely used all over the world for the prevention of postmenopausal osteoporosis, calcitonin and vitamin
D derivatives are commonly employed to treat established osteoporosis at higher age in Japan. In order to critically assess
the usefulness of vitamin D derivatives and calcitonin alone or in combination on the advancement of vertebral deformity at
higher age, 32 osteoporotic patients with vertebral deformity with the mean age of 79 were randomly divided into 4 groups
with indistinguishable age and severity of the vertebral deformity. Group 1 served as the control without specific medications
for osteoporosis. Group 2 was treated with 10 units elcatonin (eel calcitonin derivative) injected intramuscularly twice a
week. Group 3 was given 0.75 to 1.5μg/day 1α (OH) vitamin D3 orally. Group 4 was given a combination of treatments used in Groups 2 and 3.
In the lateral X-ray film of the spine taken prior to the test and every 6 months thereafter, the shape of the vertebral body
T8 through L4 was monitored by measuring the anterior, central and posterior heights. Decrease of the vertebral height ratio; anterior
or middle height/posterior or adjacent intact posterior height, by more than 20% of the original value or from above to below
0.80 both appeared to be inhibited during administration of 1α (OH) vitamin D3. Such effect seems to be augmented by simultaneous administration of elcatonin. Actual decrease of vertebral height ratio
values and the per cent fall from the original value significantly less in Groups 3 and 4 than in Group 1. Development of
vertebral deformity assessed by the changes of the vertebral height thus appears to decrease during treatment with 1α (OH) vitamin D3 especially together with calcitonin in established osteoporosis. 相似文献
39.
H Hanyu H Arai H Katsunuma R Fujita C Tomori 《Nihon Ronen Igakkai zasshi. Japanese journal of geriatrics》1991,28(2):160-165
A neuroradiological study of crossed cerebellar atrophy (CCA) was performed using X-ray CT in 103 patients suffering from unilateral supratentorial cerebrovascular diseases. CCA was demonstrated in 9 (8.7%) of 103 patients. No difference between the occurrence of CCA in cerebral hemorrhage and that in cerebral infarction was found. CCA was seen in the chronic stage of cerebrovascular disease more than 3 years since stroke occurrence, and was found to be present more frequently and to a greater extent 7 years later. No correlation between the site of bleeding and the occurrence of CCA was found. Trans-synaptic degeneration of the corticopontocerebellar tract was considered in CCA following putaminal and combined hemorrhage involving an internal capsule lesion. However, in thalamic hemorrhage, retrograde degeneration within the cerebellorubrothalamic tract was presumed. CCA following cerebral infarction was seen in patients with massive lesions in the territory of the middle cerebral artery. Multivariate analysis showed that lesions of the parietal and frontal lobes appeared to greatly contribute to the development of CCA. As the degeneration and atrophy in the thalamus on the side of the lesion appeared early and frequently, it was suggested that retrograde degeneration of the cerebellorubrothalamic tract participated, in addition to anterograde corticopontocerebellar tract degeneration, in CCA following middle cerebral artery infarction. It is likely that CCA is caused by both transsynaptic degeneration of the corticopontocerebellar tract and the cerebellorubrothalamic tract. 相似文献
40.
Ishizaki K.; Yoon D. M.; Yoshida N.; Yamazaki M.; Arai K.; Fujita T. 《British journal of anaesthesia》1995,75(5):636-638
We have studied the effect of intrathecal administration of N-methyl-D-
aspartate (NMDA) receptor antagonists on the minimum alveolar anaesthetic
concentration (MAC) of isoflurane in rats. In Wistar rats fitted with
indwelling intrathecal catheters, we determined the MAC of isoflurane after
administration of a competitive NMDA receptor antagonist, APV (0.01, 0.1,
1.0, 10, 30 micrograms), a non-competitive NMDA receptor antagonist, MK801
(0.1, 1.0, 10, 30 micrograms). NMDA (0.01, 0.1, 1.0, 10, 30 micrograms) and
saline. APV at all doses except 0.01 micrograms decreased MAC by 17.1-32%
(P < 0.001 and P < 0.0001). Although MK801 at 10 and 30 micrograms
reduced MAC by 24.3-31.7% (P < 0.001 and P < 0.0001), lower doses did
not affect MAC. Intrathecal administration of NMDA reversed these decreases
in MAC, but not to control values with APV 10 and 30 micrograms and MK801
30 micrograms. We suspect that NMDA and NMDA receptor antagonists play
important roles in the spinal cord in determining the MAC of isoflurane.
相似文献