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Cellular dehydration induced by water deprivation or hypertonic saline injection reduces feeding in a variety of species. Normal feeding in rats is maintained during isotonic saline consumption by increasing the intake of saline compared to the usual intake of water. Hamsters do not show the spontaneous preference for isotonic saline noted in rats, even after adrenalectomy. In the present investigation, feeding by hamsters was depressed during both isotonic and hypertonic saline consumption compared to the usual feeding with water. Saline intakes did not exceed water intakes under similar conditions. When fluid intakes were elevated by prior fluid deprivation, feeding rates increased at all concentrations of saline after a delay proportional to the osmolality of the solution. Positive 24-hr sodium balances were always associated with saline consumption. Water and hypertonic saline injections reduced feeding, and the fluid loads were excreted very slowly. When hamsters were fluid deprived prior to injections, saline totally suppressed feeding, while water increased feeding compared to sham injected controls. It is concluded that cellular dehydration produces a reduction of feeding in hamsters drinking isotonic or hypertonic saline. Reduced feeding with isotonic saline consumption results from the failure of hamsters to increase their ad lib intake of that solution. The prolonged retention of both sodium and fluid after saline consumption or injection suggests that further saline intake may be inhibited by an expansion of the extracellular space. 相似文献
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K. Ando N. Umetani T. Kurosawa S. Takeda Y. Katoh F. Marumo 《Journal of molecular medicine (Berlin, Germany)》1988,66(17):768-772
Summary A highly sensitive radioimmunoassay to measure atrial natriuretic peptide (ANP) concentration in urine has been established, and its clinical usefulness is presented. ANP in urine was stable at 4° C for several days and was easily measured by our radioimmunoassay. The average ANP excretion in 65 healthy persons was 25.0±1.4 ng/day (mean ± SEM) and the fractional excretion of ANP was 0.7±0.05%. In 14 patients with congestive heart failure, the average ANP excretion was 119.2±29.4 ng/day, which decreased to 53.3±11.0 after successful treatment.Abbreviations ANP
atrial natriuretic peptide
- hANP
human atrial natriuretic peptide
- RIA
radioimmunoasay
- NSB
non specific bound
- FEANP
the fractional excretion of atrial natriuretic peptide
- FENa
the fractional excretion of sodium
- SIADH
the syngrome of inappropriate secretion of antidiuretic hormone 相似文献
25.
Ultrastructural analysis of pancreatic acinar cells from mice fed on genetically modified soybean 下载免费PDF全文
Malatesta M Caporaloni C Rossi L Battistelli S Rocchi MB Tonucci F Gazzanelli G 《Journal of anatomy》2002,201(5):409-415
No direct evidence that genetically modified (GM) food may represent a possible danger for health has been reported so far; however, the scientific literature in this field is quite poor. Therefore, we investigated the possible effects of a diet containing GM soybean on mouse exocrine pancreas by means of ultrastructural, morphometrical and immunocytochemical analyses. Our observations demonstrate that, although no structural modification occurs in pancreatic acinar cells of mice fed on GM soybean, quantitative changes of some cellular constituents take place in comparison to control animals. In particular, a diet containing significant amount of GM food seems to influence the zymogen synthesis and processing. 相似文献
26.
Immunohistochemical,ultrastructural and biochemical studies of an amylase-producing breast carcinoma
Hideo Inaji Hiroki Koyama Masahiko Higashiyama Shinzaburo Noguchi Hitoshi Yamamoto Osamu Ishikawa Kaoru Omichi Takeshi Iwanaga Akira Wada 《Virchows Archiv : an international journal of pathology》1991,419(1):29-33
Summary We describe a breast cancer with ectopic production of amylase, found in the patient's serum, urine and in the tumour. Clinically, serum amylase levels reflected both the progression of the disease and regression induced by various therapies. Using agarose gel electrophoresis and a wheat protein inhibitor assay, the predominant serum amylase appeared to be identical to pancreatic-type isoenzyme. However, the action mode analysis using a new fluorogenic substrate revealed that the serum contained non-salivary, non-pancreatic amylase. The tumour had microscopic features of invasive ductal carcinoma with some argyrophilic differentiation. The component cells stained positively for amylase, and ultrastructurally numerous secretory granules were seen. 相似文献
27.
Behavioral research often requires urine collection. An apparatus has been developed for the collection of urine from individual or small groups of mice and is recommended for general use where urine from unstressed mice is required. 相似文献
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Multiple IgE-mediated sensitizations to enzymes after occupational exposure: evaluation by skin prick test, RAST, and immunoblot 总被引:1,自引:0,他引:1
We investigated 10 sensitized and 10 nonsensitized workers from a pharmaceutic factory who had been exposed to powdered trypsin, chymotrypsin, bromclain, papain, amylase, and lipase. Ten nonallergic subjects served as a control group. Titrated skin prick tests (SPT), RAST, and immunoblot studies were performed with all six enzymes. SPT reactivity revealed multiple sensitizations to proteolytic enzymes, i.e., papain (specifically sensitized/total number of sensitizations: 9/10), trypsin (8/10), chymotrypsin (8/10), and bromelain (7/10) and appeared to be more frequent and more pronounced than sensitizations to amylase (3/10) or lipase (3/10). The low molecular weight of proteolytic enzymes (20–30 kDa) and their biologic activity might facilitate mucosal penetration more easily and thus - compared to amylase and lipase - permit an immune response and induction of allergic hypersensitivity. Immunoblot studies demonstrated IgG-binding bands in both SPT-positive and -negative workers, indicating exposure to the enzymes, but not in 10 unexposed control subjects. IgE-binding bands of the enzymes were detected only in workers with a positive SPT reaction and/or a positive RAST result. IgG bands were more frequent and the IgG/IgE ratio was increased in workers without allergic complaints compared to symptomatic workers. This might indicate that high levels of specific IgG antibodies to enzymes arc associated with an immune response lacking allergic manifestations in spite of IgE-mediated sensitizations to the enzymes. Atopic subjects were at greater risk of developing IgE-mediated sensitization (7/10) and allergic symptoms to enzymes (5/7). However, even without risk of atopy, IgE-mediated hypersensitivity occurred in a few subjects (3/13) exposed to enzymes by inhalation for prolonged periods of time. 相似文献
30.
免疫-PCR法检测儿童尿中生长激素水平 总被引:1,自引:0,他引:1
目的 :建立超灵敏度的免疫 PCR法检测尿中生长激素的水平。方法 :在经戊二醛处理的PCR管中完成双抗夹心酶免疫反应 ,通过PCR扩增连接在抗原 抗体复合物上的DNA分子 ,琼脂糖电泳及扫描判断结果。结果 :处理后的PCR管完全能够进行免疫反应 ,其灵敏度可达 0 1pg ml左右。琼脂糖电泳及扫描结果表明 ,30例正常青春发育期前儿童与 1 0例经常规生长激素激发试验诊断为生长激素缺乏 (growthhormone deficient,GHD)的儿童 ,1 2h夜尿生长激素 (GH)水平有明显差异。结论 :此法的敏感度比酶标法高 1 0 3 ~ 1 0 4倍 ,适于儿童尿中微量GH水平的检测 相似文献