scholarly journals Roles of Renal Proximal Tubule Transport in Acid/Base Balance and Blood Pressure Regulation

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Motonobu Nakamura ◽  
Ayumi Shirai ◽  
Osamu Yamazaki ◽  
Nobuhiko Satoh ◽  
Masashi Suzuki ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Ang Ii ◽  
Acid Base Balance ◽  
Acid Base ◽  
Blood Pressure Homeostasis ◽  
Base Balance ◽  
Proximal Renal Tubular Acidosis ◽  
Renal Tubular ◽  
Regulation Of Blood Pressure

Sodium-coupled bicarbonate absorption from renal proximal tubules (PTs) plays a pivotal role in the maintenance of systemic acid/base balance. Indeed, mutations in the Na+-HCO3-cotransporter NBCe1, which mediates a majority of bicarbonate exit from PTs, cause severe proximal renal tubular acidosis associated with ocular and other extrarenal abnormalities. Sodium transport in PTs also plays an important role in the regulation of blood pressure. For example, PT transport stimulation by insulin may be involved in the pathogenesis of hypertension associated with insulin resistance. Type 1 angiotensin (Ang) II receptors in PT are critical for blood pressure homeostasis. Paradoxically, the effects of Ang II on PT transport are known to be biphasic. Unlike in other species, however, Ang II is recently shown to dose-dependently stimulate human PT transport via nitric oxide/cGMP/ERK pathway, which may represent a novel therapeutic target in human hypertension. In this paper, we will review the physiological and pathophysiological roles of PT transport.

Effect of Multimodal Anesthesia on the Hemodynamic Profile and Acid-Base Balance in the Early Post-Operative Period in Patients Operated for Lung Tumors

2015 ◽  
Vol 22 (4) ◽  
pp. 63-73
Author(s):  
Качур ◽  
S. Kachur ◽  
Долгих ◽  
V. Dolgikh
Keyword(s):  
Blood Pressure ◽  
Heart Rate ◽  
Ejection Fraction ◽  
Lung Tumors ◽  
Acid Base Balance ◽  
Acid Base ◽  
Arterial Blood ◽  
Post Operative Period ◽  
Base Balance ◽  
Hemodynamic Profile

This work presents the effects of multimodal anesthesia with neuraxial blockade on the basic parameters of central hemodynamics in patients operated for lung tumors, revealed by method of terapolar rheovasography by Kubicek (systolic blood pressure, diastolic, average heart rate, ejection fraction, minute volume of blood circulation, cardiac index, oxygen delivery index, the index of the total peripheral vascular resistance), as well the effects on acid‐base balance of arterial blood in the immediate post‐operative period. The level of antinociceptive protection was assessed by visual analogue scale. Comparison of results of patients operated by means of multimodal anesthesia and the patients, operated in an inhalation intravenous anesthesia with artificial lung ventilation and peri‐operative analgesia by opioid analgesics has revealed that the hemodynamic profile of the first group of patients is characterized by stability of the basic parameters such as blood pressure and heart rate, the lack of a pronounced reduction of the ejection fraction and stroke volume of the heart, despite vasoplegia caused by epidural blockade. The level of partial oxygen tension of arterial blood was decreased in the early postoperative period, but it was in the normal limits and he was statistically significantly higher than in the comparison group that can help reduce the risk of post‐operative complications. Significantly lower level of pain indicates adequate antinociceptive protection of patients.

scholarly journals Comparison between Hypertonic Saline 3% and Mannitol, the Most Commonly Used Osmotic Agents, Regarding Effect on Blood Pressure, Electrolytes Level and Acid Base Balance

2018 ◽  
Vol 86 (3) ◽  
pp. 837-842
Author(s):  
MOHAMMED H.E. HAFEZ, M.D.; GIHAN M. OBAYAH, M.D. ◽  
MAHA M.I. YOUSSEF, M.D.; MOHAMMED S. MOHAMMED, M.D. ◽  
OMNIA A. MANDOR, M.Sc.
Keyword(s):  
Blood Pressure ◽  
Hypertonic Saline ◽  
Acid Base Balance ◽  
Acid Base ◽  
Base Balance ◽  
Osmotic Agents

scholarly journals Comparing the Effects of Pre-loading with Gelatine 4% Plasma Volume Expander and 6% Hydroxyethyl Starch Solution Before Spinal Anaesthesia for Lower Limb Orthopaedic Surgery

2020 ◽  
Vol 27 (6) ◽  
pp. 68-78
Author(s):  
Nur Dyana Md Nizar ◽  
Shamsul Kamalrujan Hassan ◽  
Rhendra Hardy Mohamad Zaini ◽  
Mohamad Hasyizan Hassan ◽  
Wan Mohd Nazaruddin Wan Hassan ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Spinal Anaesthesia ◽  
Lower Limb ◽  
Orthopaedic Surgery ◽  
Venous Blood ◽  
Acid Base Balance ◽  
Acid Base ◽  
Significant Difference ◽  
Lower Limb Surgery ◽  
Base Balance

Background: Hypotension is a common complication following spinal anaesthesia. The administration of intravenous fluids prior to spinal anaesthesia, known as pre-loading, has been used to offset the hypotension effect; however, the ideal fluid for pre-loading is still a matter of debate. The objective of this study was to compare the effects of Gelaspan 4% and Volulyte 6% as pre-loading fluids. Methods: A total of 93 patients with American Society of Anaesthesiologists (ASA) physical status I or II having lower limb orthopaedic surgery under spinal anaesthesia were randomised into two groups that received either Volulyte (n = 47) or Gelaspan (n = 46). Before the spinal anaesthesia, these patients were pre-loaded with 500 mL of the fluid of their respective group. Blood samples were taken before pre-loading and again after spinal anaesthesia and sent for venous blood gas and electrolyte level measurement. Baseline and intraoperative records of systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR) and the requirement of ephedrine to treat hypotension were also recorded. Results: Both fluids could not prevent significant reductions in SBP (P = 0.011), DBP (P = 0.002) and MAP (P = 0.001). There was also significant reduction in HR over time (P < 0.001). There was no significant difference in terms of ephedrine usage between both groups. Neither Volulyte 6% nor Gelaspan 4% caused significant changes in acid-base status. Conclusion: The use of 500 mL of either Gelaspan 4% or Volulyte 6% as pre-loading fluids did not significantly prevent the incidence of post-spinal anaesthesia hypotension following orthopaedic lower limb surgery; however, both were useful in the maintenance normal acid-base balance.

Cardiorespiratory effects of prolonged angiotensin II block in resting conscious dogs

2001 ◽  
Vol 79 (9) ◽  
pp. 825-830
Author(s):  
Donald B Jennings
Keyword(s):  
Angiotensin Ii ◽  
Salt Water ◽  
Respiratory Control ◽  
Conscious Dogs ◽  
Chow Diet ◽  
Strong Ion Difference ◽  
Ang Ii ◽  
Acid Base Balance ◽  
Acid Base ◽  
Base Balance

Intravenous (iv) infusion of the angiotensin II (ANG II) receptor blocker saralasin in resting conscious dogs during physiological pertubations, such as hypotension and prolonged hypoxia, indicates the presence of an ANG II drive to increase respiration and decrease the arterial partial pressure of CO2 (PaCO2). In contrast, in eupneic resting dogs on a regular chow diet, iv infusion of saralasin for short periods (up to 30 min) provides no evidence of a tonic effect of circulating levels of ANG II on acid-base balance, respiration, metabolism, or circulation. However, ANG II influences physiological processes involving salt, water, and acid-base balances, which are potentially expressed beyond a 30 min time period, and could secondarily affect respiration. Therefore, we tested the hypothesis that blocking ANG II with iv saralasin would affect respiration and circulation over a 4-h period. Contrary to the hypothesis, iv infusion of saralasin in resting conscious eupneic dogs on a regular chow diet over a 4-h period had no effects on plasma strong ions, osmolality, acid-base balance, respiration, metabolism, or circulation when compared with similar control studies in the same animals. Thus, ANG II does not play a tonic modulatory role in respiratory control under "normal" physiological conditions.Key words: acid-base balance, arginine vasopressin, saralasin, strong ions, strong ion difference.

Two classic papers in acid-base physiology: contributions of R. F. Pitts, R. S. Alexander, and W. D. Lotspeich

2004 ◽  
Vol 287 (5) ◽  
pp. F864-F865 ◽  
Author(s):  
Gerhard Giebisch
Keyword(s):  
Acid Base Balance ◽  
Acid Base ◽  
Historical Significance ◽  
Base Balance ◽  
Renal Tubular ◽  
Classic Papers

This essay looks at the historical significance of two APS classic papers that are freely available online: Pitts RF and Alexander RS. The nature of the renal tubular mechanism for acidifying the urine. Am J Physiol 144: 239—254, 1945 ( http://ajplegacy.physiology.org/cgi/reprint/144/2/239 ). Pitts RF and Lotspeich WD. Bicarbonate and the renal regulation of acid base balance. Am J Physiol 147: 138—154, 1946 ( http://ajplegacy.physiology.org/cgi/reprint/147/1/138 ).

Complicated pregnancies in inherited distal renal tubular acidosis: importance of acid-base balance

2016 ◽  
Vol 30 (3) ◽  
pp. 455-460 ◽  
Author(s):  
Harald Seeger ◽  
Peter Salfeld ◽  
Rüdiger Eisel ◽  
Carsten A. Wagner ◽  
Nilufar Mohebbi
Keyword(s):  
Renal Tubular Acidosis ◽  
Distal Renal Tubular Acidosis ◽  
Acid Base Balance ◽  
Acid Base ◽  
Base Balance ◽  
Renal Tubular

Disturbance of acid–base balance in the young spontaneously hypertensive rat

1987 ◽  
Vol 73 (2) ◽  
pp. 211-215 ◽  
Author(s):  
P. A. Lucas ◽  
B. Lacour ◽  
D. A. McCarron ◽  
T. Drüeke
Keyword(s):  
Blood Pressure ◽  
Spontaneously Hypertensive Rat ◽  
Ionized Calcium ◽  
Acid Base Balance ◽  
Acid Base ◽  
Spontaneously Hypertensive ◽  
Plasma Bicarbonate ◽  
Blood Ph ◽  
Base Balance ◽  
Wistar Kyoto

1. The acid–base status of young spontaneously hypertensive rats (SHR) was compared with that of Wistar–Kyoto rats (WKY) in the steady state, after acid loading and after blood pressure had been maintained at normal levels from weaning. Whole blood ionized calcium was measured simultaneously. 2. In the prehypertensive stage (4 weeks of age), plasma bicarbonate was significantly lower in SHR than in WKY, while blood pH did not differ significantly. 3. After 6 weeks of age, blood pH and plasma bicarbonate were significantly lower in both anaesthetized and conscious SHR than in corresponding WKY. After 7 days administration of NH4Cl in the drinking fluid, both parameters decreased significantly in both strains and the difference in pH remained constant (0.05 pH unit, P < 0.01). 4. In none of the groups investigated did non-pH-adjusted ionized calcium differ significantly between the SHR and WKY. 5. Prevention of the development of hypertension in SHR by hydralazine treatment from weaning did not increase pH or bicarbonate compared with untreated SHR, indicating that the metabolic acidosis in the SHR was not a consequence of raised blood pressure. 6. Disturbance in acid–base balance may be involved in the pathogenesis of raised blood pressure in this animal model of genetic hypertension.

scholarly journals Effects of different plasma expanders on rats subjected to severe acute normovolemic hemodilution

2020 ◽  
Vol 7 (1) ◽  
Author(s):  
Guo-Xing You ◽  
Bing-Ting Li ◽  
Zhen Wang ◽  
Quan Wang ◽  
Ying Wang ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Hydroxyethyl Starch ◽  
The Other ◽  
Acute Normovolemic Hemodilution ◽  
Acid Base Balance ◽  
Acid Base ◽  
Base Balance ◽  
Normovolemic Hemodilution ◽  
Plasma Expanders ◽  
Low Shear

Abstract Background Plasma expanders are widely used for acute normovolemic hemodilution (ANH). However, existing studies have not focused on large-volume infusion with colloidal plasma expanders, and there is a lack of studies that compare the effects of different plasma expanders. Methods The viscosity, hydrodynamic radius (Rh) and colloid osmotic pressure (COP) of plasma expanders were determined by a cone-plate viscometer, Zetasizer and cut-off membrane, respectively. Sixty male rats were randomized into five groups with Gelofusine (Gel), Hydroxyethyl Starch 200/0.5 (HES200), Hydroxyethyl Starch 130/0.4 (HES130), Hydroxyethyl Starch 40 (HES40), and Dextran40 (Dex40), with 12 rats used in each group to build the ANH model. ANH was performed by the withdrawal of blood and simultaneous infusion of plasma expanders. Acid-base, lactate, blood gas and physiological parameters were detected. Results Gel had a lower intrinsic viscosity than HES200 and HES130 (P < 0.01), but at a low shear rate in a mixture of colloids, red cells and plasma, Gel had a higher viscosity (P < 0.05 or P < 0.01, respectively). For hydroxyethyl starch plasma expanders, the COP at a certain concentration decreases from 11.1 mmHg to 6.1 mmHg with the increase of Rh from 10.7 nm to 20.2 nm. A severe ANH model, with the hematocrit of 40% of the baseline level, was established and accompanied by disturbances in acid-base, lactate and blood gas parameters. At the end of ANH and 60 min afterward, the Dex40 group showed a worse outcome in maintaining the acid-base balance and systemic oxygenation compared to the other groups. The systolic blood pressure (SBP), diastolic blood pressure (DBP), and mean arterial pressure (MAP) decreased significantly in all groups at the end of ANH. The DBP and MAP in the Dex40 group further decreased 60 min after the end of ANH. During the process of ANH, the Dex40 group showed a drop and recovery in SBP, DBP and MAP. The DBP and MAP in the HES200 group were significantly higher than those in the other groups at some time points (P < 0.05 or P < 0.01). Conclusion Gel had a low intrinsic viscosity but may increase the whole blood viscosity at low shear rates. Rh and COP showed a strong correlation among hydroxyethyl starch plasma expanders. Dex40 showed a worse outcome in maintaining the acid-base balance and systemic oxygenation compared to the other plasma expanders. During the process of ANH, Dex40 displayed a V-shaped recovery pattern for blood pressure, and HES200 had the advantage in sustaining the DBP and MAP at some time points.

Sign in / Sign up

Export Citation Format

Share Document