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41.
The GABAB receptor agonist, baclofen, suppressed alcohol deprivation effect (a proposed experimental model of alcohol relapse) in Sardinian alcohol-preferring rats. The present study was designed to extend the characterization of the “anti-relapse” properties of baclofen to the reinstatement of alcohol-seeking behavior (another proposed model of alcohol relapse). Rats of the sP line were first trained to lever press for alcohol under a fixed ratio 4 schedule of reinforcement. Subsequently, rats were exposed to two within-session 70-min extinction/reinstatement tests with saline or baclofen administered in a counterbalanced, within-subject design. After a 60-min extinction phase, an alcohol-associated stimulus complex was presented (reinstatement phase). Saline or baclofen (3 mg/kg) were administered via a permanent intraperitoneal catheter, 30 min before the reinstatement phase. During the reinstatement phase, baclofen administration: (a) reduced by approximately 60% responses on the previously active lever, (b) increased latency to the first response and (c) decreased the response rate. These results indicate that baclofen reduced cue-induced reinstatement of alcohol-seeking behavior in sP rats.  相似文献   
42.
Gastric lipase is one of the prepancreatic lipases found in some mammalian species and in humans. Our knowledge of the hormonal regulation of gastric lipase secretion in children and adolescents is still very limited. The aim of this study was to compare the activity of human gastric lipase (HGL) in gastric juice in healthy adolescents and in patients with gastritis. The adolescents were allocated to three groups: the first including patients with Helicobacter pylori gastritis (HPG; n = 10), the second including patients with superficial gastritis caused by pathogens other than H. pylori (non-HPG; n = 14) and the control group including healthy adolescents (n = 14). Activity of HGL was measured in gastric juice collected during endoscopy. Plasma concentrations of cholecystokinin (CCK), glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) were measured in all adolescents. Activity of HGL in the non-HPG group was significantly lower than in the HPG group (p < 0.005) and the control group (p < 0.005). Mean plasma GIP levels in the control group were lower than in the non-HPG group (p < 0.003) and the HPG group (p < 0.01). We conclude that the regulation of HGL secretion by GLP-1 and CCK is altered in patients with gastritis. Moreover, GIP is a potent controller of HGL activity, both in healthy subjects and in patients with gastritis.  相似文献   
43.
Even that orodispersible tablets (ODTs) have been successfully used in therapy for more than 20 years, there is still no compendial method of their disintegration time evaluation other than the pharmacopoeial disintegration test conducted in 800–900 mL of distilled water. Therefore, several alternative tests more relevant to in vivo conditions were described by different researchers. The aim of this study was to compare these methods and correlate them with in vivo results. Six series of ODTs were prepared by direct compression. Their mechanical properties and disintegration times were measured with pharmacopoeial and alternative methods and compared with the in vivo results. The highest correlation with oral disintegration time was found in the case of own-construction apparatus with additional weight and the employment of the method proposed by Narazaki et al. The correlation coefficients were 0.9994 (p < 0.001), and 0.9907 (p < 0.001) respectively. The pharmacopoeial method correlated with the in vivo data much worse (r = 0.8925, p < 0.05). These results have shown that development of novel biorelevant methods of ODT’s disintegration time determination is eligible and scientifically justified.  相似文献   
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45.
This study tests the hypothesis that the facilitation of learning and improvement of memory observed after an intracerebroventricular (i.c.v.) injection of angiotensin II (Ang II) is, in fact, caused by its derivative angiotensin IV (Ang IV). We ran two memory tests as well as an auxiliary test assessing motor performance in rats injected (i.c.v., 1 nmol in 2 microl saline) with Ang II or Ang IV. There were separate groups receiving peptide or saline five, 10 and 15 minutes before testing. Ang IV significantly increased step-through latencies in a passive avoidance paradigm as well as improved discrimination between familiar and unfamiliar objects in an object recognition test in all groups showing better retrieval of memory of aversive as well as appetitive stimuli in the peptide-treated groups regardless of the time of its injection. In contrast, rats treated with Ang II demonstrated significant improvement of memory of aversive and appetitive stimuli in the same tests only 15 minutes after its i.c.v. injection, with no effect in the groups injected five minutes before testing and slight efficacy in those injected 10 minutes before the test. Numbers of crossings, rearings and bar approaches in an open field were similar both in the peptide-treated and control groups making it unlikely that changes in motor performance affected the memory tests. In line with the present views on the intracellular metabolism of Ang II, these results suggest degradation to Ang IV by aminopeptidases A and N is necessary before the cognitive effects can occur.  相似文献   
46.
OBJECTIVE: There is evidence that angiotensin II, the main effector of renin-angiotensin system, plays a crucial role in the pathogenesis of chronic renal injury. Angiotensin II type 1 (AT-1) receptor blockers reduce renin-angiotensin system activity by blocking the receptor, the activation of which is responsible for the majority of deleterious angiotensin II effects. The aim of the present study was to investigate renal and metabolic effects of specific AT-1 receptor blocker-losartan in patients with primary glomerulonephritis. DESIGN: Pilot clinical study. SETTING: Department of Nephrology, Transplantology and Internal Medicine, Medical University of Gdańsk, Poland. PARTICIPANTS: Fifteen patients aged 43.3 +/- 11.3 years with primary glomerulonephritis confirmed by renal biopsy were studied. INTERVENTION: Creatinine clearance, urinary excretion of protein and uric acid, urinary activity of N-acetyl-beta-D-glucosaminidase, and serum concentrations of lipids, protein, and uric acid were evaluated before and after 3 months of losartan (Cozaar; Merck Sharp & Dohme, Harlow, Essex, United Kingdom) treatment at a dose of 25 mg daily. RESULTS: We found a significant reduction of urinary excretion of protein (P <.008; average, 32%). Results also revealed a decrease of serum uric acid level (P <.01), probably as a consequence of elevated uric acid urinary excretion (P <.09). No significant changes in creatinine clearance, N-acetyl-beta-D-glucosaminidase activity, protein, or lipid levels were observed. CONCLUSION: We concluded that losartan treatment at a small dose of 25 mg daily produces antiproteinuric effect without adverse effects, notably with no decrease of glomerular filtration, and simultaneously induces beneficial changes in purine metabolism.  相似文献   
47.
AIMS: The aim of the present study was to evaluate a possible relationship between taste responses to sweet solutions and alcoholic status. METHODS: The rated intensity and pleasantness of sucrose taste was compared in male alcoholics (n = 45) and non-alcoholic controls (n = 33). RESULTS: The rated intensity, but not pleasantness, of water taste (0% sucrose) was higher in the alcoholics. The two groups did not differ with respect to the rated intensity or pleasantness of sucrose solutions (1-30%). The proportion of sweet-likers, i.e. subjects rating 30% sucrose as most pleasant, was similar in both groups (the controls: 57.6%, the alcoholics: 62.2%). A subgroup of alcoholics with a paternal history of alcoholism (n = 22) rated the highest sucrose concentration as more pleasant compared to alcoholics without alcoholic fathers. The proportion of sweet-likers among the alcoholics with a paternal history of alcoholism (77.3%) was significantly higher than that found in the alcoholics without a familial history of alcoholism (47.8%). CONCLUSIONS: The present results suggest the following: (i) alcohol dependence is not associated with any major alterations in taste responses to sucrose solutions, (ii) sweet liking is a phenotypic marker of male alcoholics with a paternal history of alcoholism.  相似文献   
48.
The analgesic effect of electrical stimulation of the hypothalamic paraventricular nucleus (PVN) was studied. Additionally, the involvement of vasopressin and opioid peptides in this process was examined by comparing vasopressin-deficient (Brattleboro) and Long-Evans rats and by administering the opiate antagonist naloxone. Rats were chronically implanted with a stimulating electrode in the parvocellular (PVN-Pc) and magnocellular (PVN-Mg) divisions of the PVN. At least 10 days after surgery, the analgesic effects of PVN stimulation were examined in lightly anesthetized rats, using the tail-flick method, and in unanesthetized rats, using the hot-plate test. PVN stimulation produced marked analgesia in both tests. Current threshold for analgesia was lower from PVN-Pc than from PVN-Mg. Threshold did not differ significantly between Brattleboro and Long-Evans rats and was not affected by naloxone administration. The results indicate that the PVN is part of the brain's pain inhibitory system, and show that the analgesia induced by PVN stimulation is not mediated by either vasopressin or opioid peptides.  相似文献   
49.
The precise morphologic characteristics of any intracardiac tumor have important implications regarding surgical planning and operative repair. Three-dimensional echocardiography has proved to be a valuable clinical technique in this field. Current methods of three-dimensional reconstruction of two-dimensional images are based on the standard gray-scale imaging technique. However, precordial gray-scale data-set information is frequently of suboptimal quality because of data degradation caused by ultrasound attenuation by chest wall structures. This has limited the use of the transthoracic three-dimensional technique to “echogenic” patients. Doppler myocardial imaging (DMI), a new ultrasound technique based on the Doppler principle, is influenced less by chest wall attenuation and in addition offers a better boundary detection algorithm for the cardiac structures. To determine if there may be a potential benefit of DMI to acquire data for three-dimensional reconstruction, a 33-year-old woman with a large intracardiac mass was studied. In this case three-dimensional gray-scale and DMI data sets were compared and contrasted with pathologic information. DMI allowed both the quantification of mass volume and the correct definition of the morphology of the mass. It was also possible to identify the precise site of attachment of the mass to the mitral valve leaflets. The information thus obtained was correlated with both operative and pathologic findings.  相似文献   
50.
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