bluuebunny/crossref_metadata_2025_split huggingface dataset:
Renal Interstitial Hydrostatic Pressure and Urinary Sodium Excretion in Rats with Angiotensin‐Converting Enzyme Inhibitor‐Induced Papillary Atrophy
Authors: Nilsson Annika B. M. , Guron Gregor S. , Adams Michael A. , Friberg Peter 
Published: May 2004

SUMMARYThe importance of angiotensin type‐1 (AT1) receptor stimulation during renal development has recently been established in both pharmacological and knockout models. We have previously reported irreversible and progressive papillary atrophy and a reduced baseline renal interstitial hydrostatic pressure (RIHP) after neonatal angiotensin‐converting enzyme (ACE) inhibition. The aim of the present study was to investigate the consequences of these abnormalities on urinary sodium excretion during acute extracellular sodium loading. Rats were treated neonatally with enalapril (10 mg kg−1 day−1) or saline control from days 3 to 23 after birth. Urinary sodium excretion was assessed in relation to mean arterial pressure (MAP) and RIHP responses in adult anaesthetised rats during moderate (1·5 and 3% body weight) and severe (9% body weight) saline‐induced volume expansion. Control rats responded to the moderate volume expansion by increasing MAP by 16 ± 6% and RIHP by 40 ± 23%, respectively. In neonatally enalapril‐treated rats, however, MAP and RIHP remained unchanged and were associated with a smaller increase in sodium excretion (44 ± 11% of the total amount infused versus 71 ± 16% for controls, P < 0·05). In contrast, severe volume expansion resulted in marked pressure rises in both the enalapril‐treated group (36 ± 12 and 112 ± 48% of baseline for MAP and RIHP, respectively) and the control group (34 ± 21 and 130 ± 34% of baseline for MAP and RIHP, respectively). Moreover, the increases in MAP and RIHP were associated with complete excretion of the severe sodium challenge within 60 min in both treatment groups. We conclude that a RIHP response appears to be a prerequisite for adequate urinary sodium excretion in this model of papillary atrophy. Hence, an intact renal medulla is not mandatory in the renal handling of sodium during extracellular loading.
Salivary Secretion of Highly Concentrated Chromogranin a in Response to Noradrenaline and Acetylcholine in Isolated and Perfused Rat Submandibular Glands
Authors: Kanno Tomio , Asada Naoto , Yanase Haruko , Iwanaga Toshihiko , Ozaki Tsuyoshi , Nishikawa Yasuko , Iguchi Kazuaki , Mochizuki Tohru , Hoshino Minoru , Yanaihara Noboru 
Published: May 2004

SUMMARYChromogranin A (CgA) is a member of a family of highly acidic proteins, chromogranins, which are co‐stored in the adrenergic neurons and paraneurons and co‐released with adrenaline and noradrenaline (NAd) in response to adequate stimulation. The present study provides novel evidence that CgA‐like immunoreactivity (IR) is stored in the exocrine cells in the granular convoluted tubule, and is secreted into saliva by stimulation with NAd and acetylcholine (ACh) in the isolated and perfused rat submandibular gland. NAd at 1 μM produced maximum secretion of CgA‐like IR (<< 0.9 mM) and a marked increase in salivary flow. Further increases in NAd concentration (10 or 100 μM) yielded concentration‐dependent decreases in both responses. ACh at 1 μM produced maximum salivary flow and a slight elevation of CgA‐like IR secretion (6 μM); 100 μM ACh decreased the salivary flow but increased the CgA‐like IR secretion (0.6 mM). Electron microscopic examination showed vigorous compound exocytosis of secretory granules in the cells of the granular convoluted tubule when the submandibular gland was stimulated with 1 μM NAd. These results provide an experimental basis for the view that the salivary CgA‐like IR secretion may be a sensitive and quantitative index of the activity of the sympathetic nervous system innervating the gland.
The Influence of Erythropoietin on the Vascular Responses of Rat Resistance Arteries
Authors: Wu Xiao Chun , Richards Nicholas T. , Johns Edward J. 
Published: May 2004

SUMMARYThis study examined the effect of erythropoietin (EPO) on resting tension and on the responses of rat mesenteric and renal arcuate arteries in vitro to a number of agonists as a possible cause of its blood pressure elevating properties when used therapeutically. Noradrenaline and potassium chloride induced concentration‐dependent vasoconstrictions in both vessel types but the basal tension, maximum tension, and the ‐log concentration producing half‐maximal response (pEC50) were altered in the presence of 0·1 or 20 U ml−1 EPO. The thromboxane A2 receptor agonist U46619 induced a constriction of the renal arcuate arteries which was enhanced by EPO at 20 U ml−1, from 1·68 ± 0·34 to 2·64 ± 0·39 mN mm−1 (P < 0·01), but which was unchanged by NG‐nitro‐L‐arginine methyl ester (10−4 m). Serotonin (10−9‐10−5 M) caused a concentration‐related vasoconstriction in renal arcuate arteries which was shifted to the right in the time control study (P < 0·001) but this was abolished by both 0·1 and 20 U ml−1 of EPO. Acetylcholine induced a relaxation of precontracted mesenteric arteries, by 95·4 ± 1·64% with an EC50 of 7·08 ± 0·08 M which was reduced (P < 0·001) by 20 U ml−1 EPO to 81·7 ± 3·56% and 6·10 ± 0·11 M, respectively. The sodium nitroprusside‐induced relaxations were unaffected by EPO. The acetylcholine‐mediated relaxations in renal arcuate arteries were unchanged by EPO. Bradykinin‐induced relaxations in mesenteric and renal arcuate arteries were unaffected by both EPO concentrations. Together these data showed that EPO over a large concentration range had only minor effects on basal tension and the vascular responsiveness of both mesenteric and renal arcuate arteries. The mechanism whereby EPO causes a chronic elevation in blood pressure is unlikely to be due to acute interactions with agonist‐mediated responses.
The Influence of Streptozotocin Diabetes and Metformin on Erythrocyte Volume and on the Membrane Potential and the Contractile Characteristics of the Extensor Digitorum Longus and Soleus Muscles in Rats
Authors: McGuire Michelle , MacDermott Mary 
Published: May 2004

SUMMARYThe effects of streptozotocin (STZ) diabetes and the antihyperglycaemic agent metformin on the contractile characteristics of the limb skeletal muscles and on erythrocyte volume were examined in rats. After 8 weeks of diabetes, the tetanic tension of the extensor digitorum longus (EDL) muscle decreased and the half‐relaxation time of the soleus muscle increased. Endurance decreased in both muscles. Metformin treatment of the diabetic rats did not prevent the development of these contractile changes. Diabetes induced depolarisation in the EDL and soleus muscles. Following exposure to insulin, both muscles repolarised. Metformin treatment of control rats induced depolarisation in the EDL and soleus muscles, but in the depolarised EDL and soleus muscles of the diabetic rats metformin treatment caused no further depolarisation. The muscles of metformin‐treated control and diabetic rats hyperpolarised in the presence of insulin. Diabetes caused an increase in the volume of the blood erythrocytes. This was prevented by metformin treatment.
Determination of an Optimal Axial‐Length Tension for the Study of Isolated Resistance Arteries on a Pressure Myograph
Authors: Coats P. , Hillier C. 
Published: May 2004

SUMMARYThe effects of longitudinal stretch on vasoreactivity were assessed in isolated, pressurised arteries from the rat mesentery, rat mid‐cerebral and human subcutaneous vascular beds. A stretch‐dependent increase in reactivity was observed only in rat third order mesenteric arteries. Longitudinal stretch >> 20% (force equal to 0.23 ± 0.04 mN) optimises vasoconstrictor responses to noradrenaline and phenylephrine in rat third order mesenteric arteries. Stretch did not affect the vasoconstriction response to depolarisation by 30 mM K+ PSS in any of the arteries studied. Similarly, stretch had no affect on pressure‐dependent myogenic responses in rat mid‐cerebral arteries. Endothelium‐independent and endothelium‐dependent mechanisms of vasorelaxation were unaffected by stretch in rat third order mesenteric arteries. Likewise, stretch did not affect vasoreactivity in rat mid‐cerebral and human subcutaneous resistance arteries. Our results show that longitudinal stretch in isobaric‐mounted rat third order mesenteric arteries is an important methodological consideration. Considering our results, we recommend that isobaric‐mounted rat third order mesenteric arteries are stretched >> 20% to provide optimal experimental conditions for pharmacological studies.
A Monocarboxylate Transporter MCT1 is Located at the Basolateral Pole of Rat Jejunum
Authors: Orsenigo M. N. , Tosco M. , Bazzini C. , Laforenza U. , Faelli A. 
Published: May 2004

SUMMARYWe have functionally expressed and identified a monocarboxylate transporter (MCT1) from rat jejunal enterocyte and we provide evidence for its basolateral localization. Poly(A)+ RNA isolated from rat jejunum was injected into Xenopus laevis oocytes and expression of a proton‐lactate symporter was investigated by means of L‐[14C]lactate uptake. The existence of an endogenous capacity for L‐lactate transport was demonstrated; when, however, oocytes were injected with jejunal mRNA, an expressed L‐lactate uptake was seen which differed from the endogenous transporter since it was significantly pH dependent. After sucrose density gradient fractionation, the highest expression of the pH‐dependent lactate uptake was detected with the mRNA size fraction of about 2‐3 kb in length. The substrate specificity, stereoselectivity and sensitivity to pCMBS (an organomercurial thiol reagent that modifies cysteine residues) of the expressed transport were in good agreement with results previously obtained using isolated jejunal basolateral membranes. Using the reverse transcriptase‐polymerase chain reaction, the presence of mRNA coding for the MCT1 isoform was demonstrated in jejunal enterocytes. These data, together with previous results, suggest that MCT1 is a major route for lactate efflux across the basolateral membrane of rat jejunum; this is in contrast to current opinion which restricts the presence of MCT1 to the apical membrane of the whole small intestine.
The Role of Nitric Oxide in Mediating Pancreatic Endocrine Responses to Insulin‐Induced Hypoglycaemia in the Conscious Calf
Authors: Edwards C. M. B. , Ghatei M. A. , Bloom S. R. , Edwards A. V. 
Published: May 2004

SUMMARYThe role of nitric oxide (NO) in mediating pancreatic endocrine responses to moderate hypoglycaemia has been investigated in conscious unrestrained calves. The synthesis of endogenous NO was inhibited by the administration of N‐nitro‐L‐arginine methyl ester (L‐NAME; 100 mg kg−1 I.A.), while sodium nitroprusside was infused continuously (2‐4 μg min−1 kg−1 I.V.) to mimic the tonic production of NO. This effectively abolished the rise in plasma pancreatic polypeptide (PP) concentration during moderate hypoglycaemia (0.7 nmol kg−1 insulin I.V.) and significantly reduced the response to more intense hypoglycaemia (2.0 nmol kg−1 insulin I.V.). In contrast, the glucagon response was not significantly affected in either group, although consistently higher plasma glucagon values were obtained in response to the higher dose of insulin following the administration of L‐NAME. It is concluded that, in the absence of L‐NAME, production of NO contributes to the PP response, but not the glucagon response to hypoglycaemia in this species under physiological conditions.
Motor Unit Discharge Characteristics during Voluntary Contraction in Patients with Incomplete Spinal Cord Injury
Authors: Smith Hazel C. , Davey Nick J. , Savic Gordana , Maskill David W. , Ellaway Peter H. , Frankel Hans L. 
Published: May 2004

SUMMARYSynchronisation of motor unit discharges is commonly seen in hand muscles of normal man but is absent following neurologically complete spinal cord injury and reduced after stroke. These findings support the notion that some corticospinal inputs to motoneurones are shared and contribute to the observed synchrony of discharge. In this study we have examined motor unit discharge in hand muscles below the level of an incomplete spinal cord injury in an attempt to relate strength of synchrony to the integrity of the corticospinal tract. Eight patients with incomplete spinal cord injury (neurological level C3‐C7) and eight control subjects took part in the study. The patients had sustained injury 14‐191 weeks prior to the recordings and had since regained good motor function in their hands. Two concentric needle electrodes were inserted into the first dorsal interosseus muscle which subjects were instructed to contract weakly so that potentials from individual motor units could be reliably identified on both recordings. Synchrony was detected by constructing cross‐correlograms between the discharges of pairs of individual motor units. The amount of synchronous firing was determined from the magnitude of any peak in the cross‐correlogram, as the probability above chance (XP) of one motor unit firing with respect to the other and vice versa. The degree of synchrony was lower (P < 0.05) in the patient group (mean XP 0.06) than in the control group (mean XP 0.09). The incidence of significant synchrony was lower in the patient group (41.8%) than in the control group (92.9%). The mean (± S.E.M.) frequency of motor unit discharge was slightly lower (P < 0.05) in patients (9.7 ± 0.4 impulses s−1) than controls (10.8 ± 0.5 impulses s−1). The mean width of synchrony peaks was narrower (P < 0.05) in patients (11.4 ± 1.1 ms) than controls (13.2 ± 0.6 ms). We conclude that the weaker synchrony of motor unit discharge in incomplete spinal cord injury may reflect permanent damage to some corticospinal axons.
Icln, An Ion Channel‐Forming Protein Associated with Cell Volume Regulation
Authors: Gschwentner M. , Fürst J. , Ritter M. , Bazzini C. , Wöll E. , Dienstl A. , Jakab M. , König M. , Scandella E. , Rudzki J. , Botta G. , Meyer G. , Lang F. , Deetjen P. , Paulmichl M. 
Published: May 2004

SUMMARYIt is not resolved whether the anionic channel involved in volume regulation after cell swelling comprises one or more subunits. Moreover, it remains to be determined which of the different proteins cloned so far, for which an involvement in cell volume regulation has been postulated, is the ideal candidate. In this review, we consider the role of the ICln protein, cloned from MDCK cells, in cell volume regulation.
The Influence of Acute Hypoxia and Carotid Body Denervation on Thermoregulation During Non‐Rapid Eye Movement Sleep in the Developing Lamb
Authors: Symonds Michael E. , Andrews David C. , Johnson Paul 
Published: May 2004

SUMMARYWe investigated the influence of ambient temperature on the thermoregulatory response to hypoxia in developing lambs before (at 4 and 14 days of age) and after (17 and 30 days of age) carotid body denervation (CBD). Lambs were studied during non‐rapid eye movement sleep at thermoneutral (23‐15°C) and cool (10‐5°C) ambient temperatures, during normoxia and acute hypoxia (inspired oxygen content of 13%). Measurements of oxygen consumption, arterial partial pressures of O2 and CO2, colonic temperature, incidence of shivering and plasma concentrations of thyroid hormones, cortisol, insulin and glucose were made under each condition. Oxygen consumption was higher at cool compared with thermoneutral ambient temperatures and decreased during hypoxia during cooling at all stages. At 4 days of age, only one lamb shivered during cooling in normoxia, but 4 out of 12 lambs shivered during hypoxia and colonic temperature fell, significantly, by 0.2°C. At 14 days, 8 out of 12 lambs shivered during cooling, of which 6 continued to shiver during hypoxia but colonic temperature did not change significantly. Plasma triiodothyronine concentrations increased on cooling at 4 and 14 days, an affect that was inhibited by hypoxia at 4, but not 14 days of age. At 17 days of age, i.e. post‐CBD, plasma thyroid hormone concentrations and oxygen consumption were lower during cold exposure compared with intact lambs at 14 days of age. In CBD lambs, imposing further hypoxia resulted in colonic temperature falling 0.6°C during cooling, with only 2 out of 10 lambs shivering. Plasma glucose and insulin, but not cortisol, concentrations decreased during hypoxia, irrespective of age or CBD. It is concluded that hypoxia has an important influence on metabolism and thermoregulation, which is modulated by age and environmental conditions. Compromised carotid body function, in lambs older than 2 weeks of age, can result in severe hypoxia and thermoregulatory dysfunction even with modest environmental cooling.
Ethical consumerism: a view from Finland
Authors: Uusitalo Outi , Oksanen Reetta 
Published: May 2004

AbstractBusiness ethics and corporate social responsibility have gained more attention in recent years. However, the consumers’ perspective on ethics is still a little researched area. This study reports a survey (n = 713) on the views of Finnish consumers about ethics in trade. Consumers’ willingness to promote business ethics as well as the obstacles to ethical consumption are investigated. The results of the study show that while the majority of the respondents regard business ethics as important, this attitude does not translate into their choice behaviour. Consumers are uncertain about which products and firms follow ethical rules and which do not. The most important obstacles to ethical consumption were difficulties in obtaining information, problems in product availability and high prices of ethical products.
Measuring physical access to ‘healthy foods’ in areas of social deprivation: a case study in Cardiff
Authors: Guy Clifford M. , David Gemma 
Published: May 2004

AbstractThis paper examines some characteristics of ‘food deserts’– areas of social deprivation which have poor physical access to food shopping – in a large British city, Cardiff. The stereotype of the ‘food desert’ is critically examined, emphasizing the importance attached by residents of such areas to easy access to food shopping, especially in multiple supermarkets. The case study of Cardiff briefly discusses the identification of potential ‘food deserts’, and then examines the structures of ‘healthy food’ availability and prices in four areas of the city (two in the inner city, two in the outer city) where physical access to large multiple supermarkets is poor. The analysis shows that the local shops in these areas cannot compete generally with large supermarkets on either availability of items or their prices, but that the local shops in the inner city areas are rather more competitive than those in the outer areas. Implications for research and policy formulation are finally discussed.
Food choice, nutrition education and parental influence on British and Korean primary school children
Authors: McCullough Fiona S.W. , Yoo Seunghee , Ainsworth Paul 
Published: May 2004

AbstractThe nutritional status of children can influence their health and the risk factors for developing chronic diseases later in life. Korea is unique in that it is relatively westernized and yet maintains much of the traditional foods and cooking methods. Effective nutrition education should help children to choose a healthy diet through the establishment of positive dietary practices and habits. The main purpose of this research is to compare awareness towards nutrition education between primary schools in the UK and Korea and nutritional knowledge that children and parents have in these countries. Dietary and healthy eating knowledge data were collected by a questionnaire as part of a case study comparison using one primary school in Manchester, UK, and one in Seoul, Korea. A total of 171 primary school children and 124 parents of the children were recruited. The results indicated that children and parents appeared to be aware of the importance of limiting fat, sodium and sugar intakes, and requiring non‐starch polysaccharide (NSP). However, in the case of some foods they did not have satisfactory nutritional knowledge of which foods were high in fat, salt, sugar and NSP. British children had a better understanding of the health implication of fat than Korean children, whereas more Korean children considered excessive salt intake harmful than British children. There seemed to be differences in dietary pattern and familiarity with food between the two countries. Children identified parents as the main source of nutritional information. Therefore, parents as well as children need to learn about nutrition in order to give appropriate information or advice to improve the diets of their children. Children preferred exciting, fun, positive and a practical approach to learning about nutrition, such as computer packages and cookery classes. Parents wanted schools to give their children more information about nutrition. This research has shown that nutrition education in schools should be concerned not only to provide nutritional knowledge but also to encourage children to choose healthy food by redesigning nutrition education and school meals.
The role of dietary information in women's whole milk and low‐fat milk intakes
Authors: Kim Sora , Douthitt Robin A. 
Published: May 2004

AbstractThis study examines the effects of dietary information on women's whole and low‐fat milk intakes. The sample is 1928 female meal planners aged 20 years or over who provided information on their milk intake for 2 days in the 1994–96 Continuing Survey of Food Intakes by Individuals and who completed the 1994–96 Diet and Health Knowledge Survey in the follow‐up interview. The nested Tobit model was used to handle the sequentially censored data. Women's dietary information contributed to reduced whole milk consumption and increased low‐fat milk consumption indicating different effects on whole milk and low‐fat milk consumption.
Product attributes and consumer acceptance of nutritionally enhanced genetically modified foods
Authors: Hossain Ferdaus , Onyango Benjamin 
Published: May 2004

AbstractUsing data from a national survey, this study analyses US consumers’ acceptance of genetically modified foods that provide additional nutritional benefits. Using an ordered probit model, this study examines the relation between the willingness to consume genetically modified foods and consumers’ economic, demographic and value attributes. Empirical results suggest that despite having some reservations, especially about the use of biotechnology in animals, American consumers are not decidedly opposed to food biotechnology. Consumers’ economic and demographic variables are only weakly related to their acceptance of food biotechnology, especially when technology involves plant‐to‐plant DNA transfer. However, public trust and confidence in various private and public institutions are significantly related to their acceptance of food biotechnology. Overall, consumer acceptance of bioengineered foods is driven primarily by public perceptions of risks, benefits and safety of these food products.