Role of Glutamate on Ammoniagenesis from Glutamine in Acute Metabolic Acidosis

2015 ◽  
pp. 124-129
Author(s):  
Kazutomo Ujiie ◽  
Hiroshi Nonoguchi ◽  
Kimio Tomita ◽  
Fumiaki Marumo
Keyword(s):  
Metabolic Acidosis ◽  
Acute Metabolic Acidosis

Skeletal buffering of acute metabolic acidosis

1975 ◽  
Vol 229 (6) ◽  
pp. 1618-1624 ◽  
Author(s):  
JA Bettice ◽  
Gamble JL
Keyword(s):  
Metabolic Acidosis ◽  
Soft Tissue ◽  
Sodium Content ◽  
Long Bones ◽  
Exchangeable Sodium ◽  
Acid Infusion ◽  
Bone Water ◽  
Acute Metabolic Acidosis

Decreases in the sodium content of bone were measured to evaluate the role of this tissue in the buffering of acute metabolic acidosis. The bones of rats and dogs were labeled with radiosodium prior to the infusion of HCl, and changes in the radioactivity were used to indicate the loss of bone sodium. Significant reductions in the skeletal sodium occurred within the first 5 h of acidosis, and these losses can only be partially attributed to the hyponatremia accompanying the acid infusion. Decreases were greatest in the smaller bones of the rat; and, in the dog, the losses from flat bones exceeded those of the long bones. Only the rapidly exchangeable sodium of bone was involved in the changes due to acidosis. Soft tissue buffering may be more important initially; during 1.5-h experiments, the skeletal losses were small and could be ascribed almost entirely to the decrease in the amount of sodium contained in bone water. However, at the end of 5.0 h, the quantity of sodium released from the skeleton is sufficient to account for much of the tissue buffering.

Role of acidosis-induced increases in calcium on PTH secretion in acute metabolic and respiratory acidosis in the dog

2004 ◽  
Vol 286 (5) ◽  
pp. E780-E785 ◽  
Author(s):  
Ignacio López ◽  
Escolástico Aguilera-Tejero ◽  
José Carlos Estepa ◽  
Mariano Rodríguez ◽  
Arnold J. Felsenfeld
Keyword(s):  
Parathyroid Hormone ◽  
Metabolic Acidosis ◽  
Specific Effect ◽  
Respiratory Acidosis ◽  
Normal Value ◽  
Baseline Values ◽  
Acute Metabolic Acidosis ◽  
Sufficient Magnitude ◽  
Edta Infusion

Recently, we showed that both acute metabolic acidosis and respiratory acidosis stimulate parathyroid hormone (PTH) secretion in the dog. To evaluate the specific effect of acidosis, ionized calcium (iCa) was clamped at a normal value. Because iCa values normally increase during acute acidosis, we now have studied the PTH response to acute metabolic and respiratory acidosis in dogs in which the iCa concentration was allowed to increase (nonclamped) compared with dogs with a normal iCa concentration (clamped). Five groups of dogs were studied: control, metabolic (clamped and nonclamped), and respiratory (clamped and nonclamped) acidosis. Metabolic (HCl infusion) and respiratory (hypoventilation) acidosis was progressively induced during 60 min. In the two clamped groups, iCa was maintained at a normal value with an EDTA infusion. Both metabolic and respiratory acidosis increased ( P < 0.05) iCa values in nonclamped groups. In metabolic acidosis, the increase in iCa was progressive and greater ( P < 0.05) than in respiratory acidosis, in which iCa increased by 0.04 mM and then remained constant despite further pH reductions. The increase in PTH values was greater ( P < 0.05) in clamped than in nonclamped groups (metabolic and respiratory acidosis). In the nonclamped metabolic acidosis group, PTH values first increased and then decreased from peak values when iCa increased by >0.1 mM. In the nonclamped respiratory acidosis group, PTH values exceeded ( P < 0.05) baseline values only after iCa values stopped increasing at a pH of 7.30. For the same increase in iCa in the nonclamped groups, PTH values increased more in metabolic acidosis. In conclusion, 1) both metabolic acidosis and respiratory acidosis stimulate PTH secretion; 2) the physiological increase in the iCa concentration during the induction of metabolic and respiratory acidosis reduces the magnitude of the PTH increase; 3) in metabolic acidosis, the increase in the iCa concentration can be of sufficient magnitude to reverse the increase in PTH values; and 4) for the same degree of acidosis-induced hypercalcemia, the increase in PTH values is greater in metabolic than in respiratory acidosis.

Effect of acidosis on PTH-dependent renal adenylate cyclase in phosphorus deprivation: role of G proteins

1990 ◽  
Vol 258 (6) ◽  
pp. F1640-F1649
Author(s):  
E. Bellorin-Font ◽  
R. Starosta ◽  
C. L. Milanes ◽  
C. Lopez ◽  
N. Pernalete ◽  
...  
Keyword(s):  
Metabolic Acidosis ◽  
Adenylate Cyclase ◽  
Maximal Activity ◽  
Phosphate Deprivation ◽  
Adp Ribosylation ◽  
Phosphate Depletion ◽  
Cortical Membranes ◽  
And Function ◽  
Gs Alpha

These studies examine the regulation of adenylate cyclase in renal cortical membranes from phosphate-deprived and phosphate-deprived acidotic dogs. Enzyme stimulation by parathyroid hormone (PTH) was decreased in phosphate deprivation [Vmax 1,578 +/- 169 vs. 2,581 +/- 219 pmol adenosine 3',5'-cyclic monophosphate (cAMP).mg protein-1 x 30 min-1 in controls, P less than 0.01]. Metabolic acidosis further decreased PTH-stimulated activity. Membranes from phosphate-deprived dogs showed a decrease in Gs alpha-content by cholera toxin-dependent ADP-ribosylation (174 +/- 18 arbitrary units vs. 266.4 +/- 13.6 in controls, P less than 0.01). Metabolic acidosis further decreased Gs alpha-content, P less than 0.01. Gi content by pertussis-dependent ADP-ribosylation was also lower in phosphate-deprived and phosphate-deprived acidotic animals. Gs function was examined by its property to protect the catalytic unit from inactivation by N-ethylmaleimide when preincubated with GTP gamma S. In controls, protection of inactivation was 80% of the maximal activity, whereas in phosphate deprivation protection was less than 50%. In conclusion, metabolic acidosis enhances adenylate cyclase resistance to PTH in phosphate deprivation. These alterations are associated with a decrease in the content and function of Gs alpha, suggesting a role of Gs in the renal adaptation to phosphate depletion and acidosis.

scholarly journals Metabolic Acidosis in Patients with CKD: Epidemiology, Pathogenesis, and Treatment

2021 ◽  
pp. 1-16
Author(s):  
Marcin Adamczak ◽  
Stanisław Surma
Keyword(s):  
Metabolic Acidosis ◽  
Sodium Bicarbonate ◽  
Current Knowledge ◽  
Venous Blood ◽  
The Body ◽  
Hydrogen Ions ◽  
Ckd Progression ◽  
New Drug ◽  
Treatment And Prevention

<b><i>Background:</i></b> Metabolic acidosis in CKD is diagnosed in patients with plasma or venous blood bicarbonate concentration lower than 22 mmol/L. Metabolic acidosis occurs in about 20% of patients with CKD. Metabolic acidosis may lead to dysfunction of many systems and organs as well as CKD progression. Currently, sodium bicarbonate is mainly used for pharmacological treatment of metabolic acidosis in patients with CKD. Veverimer is a new drug dedicated to treatment of metabolic acidosis in patients with CKD. Orally given veverimer binds hydrogen ions in the intestines and subsequently is excreted from the body with feces. Clinical studies have shown that veverimer is effective in increasing serum bicarbonate concentrations in CKD patients with metabolic acidosis. Here, we present review of the epidemiology, pathogenesis, diagnosis, treatment, and prevention of metabolic acidosis in CKD patients. <b><i>Summary:</i></b> Metabolic acidosis is common in patients with CKD and contributes to CKD progression and many complications, which worsen the prognosis in these patients. Currently, sodium bicarbonate is mainly used in metabolic acidosis treatment. The role of the new drug veverimer in the metabolic acidosis therapy needs further studies. <b><i>Key Message:</i></b> The aim of this review article is to summarize the current knowledge concerning the epidemiology, pathogenesis, diagnosis, treatment, and prevention of metabolic acidosis in CKD patients.

scholarly journals ACUTE METABOLIC ACIDOSIS: EFFECTS ON ARGININE IN VASOPRESSIN(AVP) RELEASE IN FETAL SHEEP

1984 ◽  
Vol 18 ◽  
pp. 137A-137A
Author(s):  
Daniel J Faucher ◽  
Tom Lowe ◽  
About Laptook ◽  
John C Porter ◽  
Charles R Rosenfeld
Keyword(s):  
Metabolic Acidosis ◽  
Fetal Sheep ◽  
Acute Metabolic Acidosis
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