Issue 4, 2010 October 2010 Welcome to the fourth issue of Kidney and Blood Pressure Research Digest (KBPR Digest) in 2010. We would like to draw your attention to articles of outstanding importance in the field of nephrology and hypertension, presenting short summaries of these articles to the scientific community in the form of KBPR Digest. KBPR Digest provides readers from all over the world with a free and concise overview on interesting topics which are part of the current issue of Kidney and Blood Pressure Research. We hope that you will be inspired to get to know more about the articles which are presented below. Professor Thomas Quaschning, MD, PHD In behalf of the Editorial Board of Kidney and Blood Pressure Research mail@thomas-quaschning.de   Digest of issue 4/2010 Issue 4/2010 of Kidney and Blood Pressure Research covers a wide spectrum of clinical and preclinical topics. It contains a study which explores the impact of maternal protein restriction on angiotensin receptor expression in the fetal rat kidney as well as an analysis of the effect of acupressure on thirst in hemodialysis patients. A third study evaluates the effects of anemia, uremia and the combination of both on the cardiovascular system in an animal model. Numerous epidemiological studies have shown an association between poor nutrition during pregnancy and an increased risk of developing cardiovascular disease in adulthood. Similarly, in the laboratory rat poor nutrition in the form of modest protein restriction during pregnancy results in the development of hypertension in the offspring. This phenomenon has become known as the developmental programming of cardiovascular disease. Rats exposed to a low-protein diet in utero have proportionally smaller kidneys with a reduced number of nephrons. Renal renin levels are reduced at birth. However, by weaning renin, angiotensin II and aldosterone concentrations are restored to control levels. Furthermore, renal angiotensin II AT1 and AT2 receptor subtype expression is increased leading to greater hemodynamic sensitivity to exogenous angiotensin II. The aim of the present study by Alwasel and colleagues (Kidney Blood Press Res 2010;33:251-259) was to determine the expression of both angiotensin receptor subtypes during nephrogenesis. Pregnant Wistar rats were fed either control 18% protein diet or low 9% protein diet (LP). A 35% reduction in nephron number associated with a 50% reduction in total glomerular volume was demonstrated by the authors in LP rats. Renal AT 1 and AT 2 receptor protein expression was significantly lower in LP rats. AT 1 expression in LP rat kidneys tended to increase after weaning while AT 2 expression declined until day 10, when it began to increase again. Since angiotensin receptor expression was reduced during late gestation and in early postnatal life - before nephrogenesis is completed - angiotensin II-regulated cell proliferation may be disturbed in the LP rat kidney contributing to the reduction in nephron number. Finally, maternal protein restriction leads to an elevation in blood pressure in the newborn, validating this experimental setting as a model for programmed hypertension which warrants further detailed investigation. Thirst or dry mouth is one of the most frequently occurring symptoms in hemodialysis (HD) patients. Studies report that 60-90% of HD patients experience exaggerated thirst and dry mouth. The symptom of thirst can cause significant distress. Importantly, thirst is also associated with a higher large interdialytic weight gain (IWG). A large IWG can result in enhanced risk for cardiovascular morbidity, the main cause of death in end-stage renal disease (ESRD) patients. Patients undergoing HD must follow specific treatment regimens, one of which is limiting fluid intake to avoid high IWG. While adhering to fluid restriction is very important for HD patients, studies on the self-care behaviors involving HD patients from both western and eastern countries have indicated that only between 32 and 74% of patients adhere to recommended fluid intake. There are likely to be a number of reasons why patients do not adhere to fluid restrictions, including the distress the patient may experience from severe thirst. A limited number of studies have explored interventions to manage the symptom of thirst. Studies report that ESRD patients undergoing HD exhibit lower salivary flow rates than healthy subjects. The study presented by Yang et al. (Kidney Blood Press Res 2010;260-265) evauates the effect of an acupressure program on HD patients' thirst and salivary flow rates. The acupressure program included placebo, followed by true acupressure, each applied for 4 weeks. Twenty-eight patients first received a sticker as placebo acupressure at two acupoints CV23 and TE17 three times a week for 4 weeks, and then received true acupressure in the same area for the next 4 weeks. Salivary flow rate and thirst intensity were measured at baseline, during and after treatment completion for both the placebo and true acupressure programs. The authors reported that the true acupressure program was associated with a significantly increased salivary flow rate. The mean thirst intensity as assessed by a verbal rating scale also improved significantly after treatment completion in HD patients. There was no statistically significant difference in pre-post program salivary flow rate; however, significant improvement in thirst intensity scores was observed in the placebo acupressure program. In conclusion, this study provides preliminary evidence that acupressure may be effective in improving salivary flow rates and thirst intensity. Even though the study has some methodological limitations, further attempts may be warranted to bring relief to thirsty HD patients by non traditional approaches. Anemia is a well-known regular feature of chronic renal failure (CRF) and has been documented to be an important cardiovascular risk factor in CRF both in experimental and in clinical studies. Recently, the joint occurrence of cardiovascular disease, kidney disease and anemia has been termed the 'cardio-renal anemia syndrome'. Since recombinant human erythropoietin became available, anemia has been increasingly recognized as an adverse risk factor for patient morbidity and mortality. It was the aim of the present study by Jürgensen and colleagues (Kidney Blood Press Res 2010;33:274-281) to clarify whether uremia and anemia are additive or supra-additive with respect to cardiovascular alterations. For this purpose, 30 Sprague-Dawley rats were sham operated (sham) or subtotally nephrectomized (SNX). Both groups were subdivided into anemic (target hemoglobin 10 g/dl, by tail artery punctures) and untreated animals. Blood pressure, echocardiographic measurements and morphometric investigations were performed. The study was terminated after 16 weeks. Heart rate and blood pressure were found to be similar in all groups. Anemia was comparable in sham+anemia and SNX+anemia. Left ventricular end-diastolic pressure was significantly higher in untreated SNX and SNX+anemia than in sham. Anemia and SNX caused comparable left ventricular hypertrophy (LVH), which was significantly higher in SNX+anemia. In sham animals, anemia induced thickening of intramyocardial arteries, which was significantly more pronounced in SNX with no additional effect of anemia. The authors conclude that under experimental conditions, anemia and CRF induced LVH and intramyocardial arteriolar thickening. If both are combined, the increase in LVH is even more marked, whereas there are no additional effects on intramyocardial structural alterations. Transferred to clinical conditions the present data emphasize that anemia is definitely not a benign condition and can obviously induce cardiovascular alterations. In combination with CRF, however, there are possibly, but not necessarily, additive effects, and therefore correction of anemia may not always lead to cardiovascular benefits. For submission of articles or sign-ups to ToC Alerts, please go to the journal's homepage © S. Karger AG - Medical and Scientific Publishers Allschwilerstrasse 10, P.O. 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