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31.
Miroslaw Szmidr Marek L. Kowalski Iwona Grzelewska-Rzymowska Jerzy Rozniecki 《Allergy》1983,38(1):43-48
The influence of acetylsalicylic acid (ASA) on skin response to intradermal injection of compound 48/80 and histamine was studied in order to determine whether ASA elicits any abnormalities also in the skin of asthmatics reacting with bronchoconstriction to ingestion of this drug.
The applied ASA dose (mean dose 150 mg) elicited bronchoconstriction in all 16 patients with asthma and ASA sensitivity (mean fall of FEV1 34%) and increased the weal response to compound 48/80 to about 51% (P>0.05) as compared with the response before the ASA-challenge, In asthmatic persons without ASA sensitivity a 150 mg ASA dose did not influence the skin response to any of the reagents. On the other hand, a 600 mg dose decreased skin response to histamine and compound 48/80 in persons without ASA intolerance, although the decrease was statistically significant only in the flare after compound 48/80 (P>0.05).
The authors believe that additional local defect is needed to reveal sensitivity to ASA in the skill of ASA-sensitive asthmatics, just as bronchial hyperreactivity is indispensible for revealing the action of ASA in the bronchi. 相似文献
The applied ASA dose (mean dose 150 mg) elicited bronchoconstriction in all 16 patients with asthma and ASA sensitivity (mean fall of FEV
The authors believe that additional local defect is needed to reveal sensitivity to ASA in the skill of ASA-sensitive asthmatics, just as bronchial hyperreactivity is indispensible for revealing the action of ASA in the bronchi. 相似文献
32.
The ingestive responses of rats given celiac vagotomy (C), combined celiac and hepatic vagotomy (CH), or low total vagotomy (removal of all tissue from around the esophagus, stomach and duodenum; LT) were compared with sham operated controls (S) in a series of regulatory challenges. The vagotomized groups responded normally to 2-deoxy-D-glucose (2DG; 125, 250, 500 mg/kg, IP), insulin (4, 8, 12 U/kg, IP), and polyethylene glycol (10 ml/kg: 30% w/v, SC), but displayed attenuated responses to epinephrine (40, 80, 120 micrograms/kg, IP) and hypertonic saline (10 ml/kg: 0.25, 0.5, 1.0 M, IP). These results can be interpreted as evidence that the celiac vagus carries a major component of hepatic afferent innervation. Additionally, when considered with other findings they suggest that whereas the anorectic activity of epinephrine is mostly confined to the liver, 2DG hyperphagia involves stimulation of a wider population of peripheral metabolic receptors. 相似文献
33.
Spontaneous meal sizes, intermeal intervals, and 24 hr feeding rhythms were monitored in normal and 60 day recovered vagotomized rabbits fed solid laboratory chow. Mean sizes of meals and intermeal intervals, and the circadian distribution of food intake did not differ between the two groups, but vagotomy was associated with increased frequencies of both smaller and larger than average meals. Positive meal to postmeal interval correlations were evident in intact but not vagotomized animals, whereas vagotomized animals displayed a meal to premeal interval correlation in the light phase that was not present in normal rabbits. 相似文献
34.
Self-selection of dietary casein and soy-protein by the cat 总被引:1,自引:0,他引:1
Growing specific-pathogen-free kittens were fed for two weeks a choice between two complete diets differing only in protein content. When casein diets containing 18, 36 and 54% protein were offered in the three possible combinations, the kittens consistently avoided the higher casein diets and kittens offered the two highest levels of casein significantly reduced their total food intake. In one soy-protein choice study, 16, 31 and 63% protein diets were each offered with a protein-free (PF) diet. When diets were similar in physical consistency, kittens selected similar amounts of both diets with the result that the PF:16% group consumed below their requirement of protein. In another soy-protein experiment the 16, 31 and 63% protein diets were offered in their three possible combinations. Kittens in all three groups selected similar amounts of both diets. Except for their avoidance of casein, the kittens did not regulate in a consistent manner their intake of protein and therefore, behaved very differently from the rat in the self-selection of dietary protein. 相似文献
35.
Alexander Nikolaevih Kravtsov Yutaka Oomura Konstantin Viktorovih Sudakov 《Pathophysiology》2002,8(4):255-258
We studied the sensitivity of sensorimotor cortex neurons in rabbits to microiontophoretic administration of antibodies against acid fibroblast growth factor (anti-aFGF). Spontaneous activity and reaction of neurons to electrical stimulation of ‘feeding centers’ in the lateral hypothalamic area (LHA) were recorded. We analyzed impulse activity of 52 neurons in the sensorimotor cortex. It was shown that 14 neurons (25%) reacted to microiontophoresis of anti-aFGF (excitation and inhibition in 9 and 5 neurons, respectively). Microiontophoretic administration of anti-aFGF did not change the reaction (excitation or inhibition) of 27 neurons to electrical stimulation of LHA. Initially, 14 neurons did not response to LHA stimulation. After microiontophoretic administration of anti-aFGF, 6 of 14 neurons displayed pronounced reactions to electrical stimulation of LHA (excitation and inhibition in 2 and 4 neurons, respectively). These data suggest that aFGF plays an important physiological role in feeding motivations. 相似文献
36.
M B Essatara J E Morley A S Levine M K Elson R B Shafer C J McClain 《Physiology & behavior》1984,32(3):475-478
Anorexia is a major symptom of zinc deficiency, but the mechanism(s) for this anorexia are poorly defined. Recent studies have suggested an integral role for endogenous opiate peptides in appetite regulation. Dynorphin, a leucine-enkephalin containing opiate peptide, is a potent inducer of spontaneous feeding. In this study we showed that zinc deficient animals were relatively resistant to dynorphin-induced feeding. Measurement of dynorphin levels using a highly sensitive radioimmunoassay showed that zinc deficient animals had lower levels of dynorphin in the hypothalamus than did ad lib fed animals, with weight restricted animals having intermediate values. [3H]-naloxone binding was significantly increased to isolated brain membranes from zinc deficient animals using 1 nM unlabeled naloxone when compared to ad lib fed controls with the weight restricted animals again having intermediate values. These data suggest that abnormalities in endogenous opiate regulation of appetite may well play a role in the anorexia of zinc deficiency. The effects of zinc deficiency on endogenous opiate action appear to include alterations in receptor affinity, a post-receptor defect and alterations in the synthesis and/or release of dynorphin. 相似文献
37.
Rats equipped with tubes leading to their stomach, duodenum or jejunum were infused with a liquid diet for 9 hr (4 ml/hr) and were allowed to eat during the last 8 hr of infusion. All rats ate significantly less on diet infusion days than on saline or no infusion days. A second study showed that a taste aversion could not be conditioned to flavored water associated with diet infusion. Apparently, intrajejunal injection of nutrients produces satiety and not discomfort. Infusion of the diet for 5 consecutive days into the stomach, duodenum or jejunum consistently and significantly lowered food intake by reducing meal size, not meal frequency. Results suggest that the small intestine below the infusion site contributes to normal satiety. 相似文献
38.
A monitoring system to continuously record the daily pattern of drinking and eating of rats is described. This system, based on a North Star microcomputer, can record the amount of food ingested with a temporal resolution of +/- 1.0 second and quantitative accuracy within +/- 5%. Drinking behavior is detected using a drinkometer which also has a temporal resolution of +/- 1.0 second. Data are analyzed by computer to determine absolute amounts of consumption and patterns of intake. The patterns of feeding and drinking recorded by this system are similar to those observed using other monitoring devices. 相似文献
39.
Characterization of allergens in Apiaceae spices: anise, fennel, coriander and cumin 总被引:1,自引:0,他引:1
E. JENSEN-JAROLIM A. LEITNER R. HIRSCHWEHR D. KRAET B. WÜTHRICH O. SCHEINER J. GRAF C. EBNER 《Clinical and experimental allergy》1997,27(11):1299-1306
Background Symptoms elicited by IgEmediated food allergy range from mild local to severe systemic reactions. Allergens in spices are particularly dangerous due to their hidden presence in many dishes. Objectives and Methods According to clinical observations, mugwort and birch pollen allergy, and hypersensitivity to spices are frequently associated, but the crossreacting compounds were not defined so far. We tested sera of 15 patients who experienced adverse reactions to spiced food and characterized their IgE-binding patterns on anise, fennel, coriander and cumin extracts through immunoblot and inhibition experiments. Results The use of anti-Bet v 1 (MoAb) and anti-profilin (rabbit) antibodies revealed the presence of crossreacting allergens in the tested spice extracts. Inhibition experiments showed that IgE-binding to allergens in Apiaceae spices could be blocked by preincubation of sera with rBet v I or rBet v 2 (birch profilin). Moreover, we detected crossreacting allergenic molecules in the molecular weight range of 60kDa. IgE-binding to spice allergens occurred only with sera of 10/15 (66%) patients with allergy to pollen (birch, niugwort) and/or celeriac. In five out of 15 (33%) patients with a history of adverse reaction to spices, but without pollen and celeriac allergy, no IgE-binding to any spice protein could be demonstrated. It is possible that these clinical reactions could bo elicited by other types of hypersensitivity (Type II. IIII, IV), however, as spices contain highly reactive substances, the symptoms may most likely be classified as food-intolerant. Conclusions Bet v 1- and profilin-related allergens may, besides higher molecular weight allergenic molecules, be responsible for Type I allergy to anise, fennel, coriander or cumin, members of the Apiaceae. 相似文献
40.
Soszynski D 《Physiology & behavior》2002,76(1):159-169
The role of nitric oxide (NO) was investigated in endotoxin (lipopolysaccharide, LPS) tolerance in freely moving biotelemetered rats. We monitored changes in febrile response and feeding behavior (food intake, water intake) during the development of tolerance to repeated intraperitoneal injections of LPS (50 microg/kg) along with injections of N(omega)-nitro-L-arginine methyl ester (L-NAME; 50 mg/kg), an inhibitor of NO synthase. Rats were treated with LPS and L-NAME for three consecutive days. On the fourth day, all rats were injected with LPS alone. Control rats were injected with saline along with saline or with L-NAME for four consecutive days. Rats repeatedly injected with LPS became tolerant to pyrogenic and hypophagic/cachexic effects of LPS as early as on the second day of experiment. The treatment with L-NAME prevented the attenuation of febrile response following the second LPS injection. Moreover, the depressive effects of LPS on body weight as well as on water and food intake were prolonged in rats treated with a combination of L-NAME and LPS. Injection of LPS caused a 3.5-fold increase in plasma nitrite within 3 h and nitrite levels remained significantly elevated 6 and 24 h after LPS. Rats injected secondly with LPS did have still 2.5- to 3-fold increase in plasma nitrite levels 3 and 6 h, but not 24 h, after injection. Third injection of LPS did not elevate nitrite level in plasma. Taken together, presented data provide clear evidence that NO formation is involved in mechanisms responsible for development of early-stage tolerance to endotoxin. 相似文献