1
|
Rimer JD, Sakhaee K, Maalouf NM. Citrate therapy for calcium phosphate stones. Curr Opin Nephrol Hypertens 2020; 28:130-139. [PMID: 30531474 DOI: 10.1097/mnh.0000000000000474] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW Calcium phosphate (CaP) stones represent an increasingly encountered form of recurrent nephrolithiasis, but current prophylactic medical regimens are suboptimal. Although hypocitraturia is a well-described risk factor for CaP stones, strategies that enhance citrate excretion have not consistently been effective at reducing CaP saturation and stone recurrence. This review summarizes the role of citrate therapy in CaP nephrolithiasis. RECENT FINDINGS Citrate in urine inhibits CaP stone formation through multiple mechanisms, including the formation of soluble citrate-calcium complexes, and inhibition of CaP nucleation, crystal growth and crystal aggregation. Recent in-vitro studies demonstrate that citrate delays CaP crystal growth through distinct inhibitory mechanisms that depend on supersaturation and citrate concentration. The impact of pharmacological provision of citrate on CaP saturation depends on the accompanying cation: Potassium citrate imparts a significant alkali load that enhances citraturia and reduces calciuria, but could worsen urine pH elevation. Conversely, citric acid administration results in minimal citraturia and alteration in CaP saturation. SUMMARY Citrate, starting at very low urinary concentrations, can significantly retard CaP crystal growth in vitro through diverse mechanisms. Clinically, the net impact on CaP stone formation of providing an alkali load during pharmacological delivery of citrate into the urinary environment remains to be determined.
Collapse
Affiliation(s)
- Jeffrey D Rimer
- Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas
| | - Khashayar Sakhaee
- Department of Internal Medicine, and Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| | - Naim M Maalouf
- Department of Internal Medicine, and Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas, USA
| |
Collapse
|
2
|
Sakhaee K, Maalouf NM, Sinnott B. Clinical review. Kidney stones 2012: pathogenesis, diagnosis, and management. J Clin Endocrinol Metab 2012; 97:1847-60. [PMID: 22466339 PMCID: PMC3387413 DOI: 10.1210/jc.2011-3492] [Citation(s) in RCA: 145] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
CONTEXT The pathogenetic mechanisms of kidney stone formation are complex and involve both metabolic and environmental risk factors. Over the past decade, major advances have been made in the understanding of the pathogenesis, diagnosis, and treatment of kidney stone disease. EVIDENCE ACQUISITION AND SYNTHESIS Both original and review articles were found via PubMed search reporting on pathophysiology, diagnosis, and management of kidney stones. These resources were integrated with the authors' knowledge of the field. CONCLUSION Nephrolithiasis remains a major economic and health burden worldwide. Nephrolithiasis is considered a systemic disorder associated with chronic kidney disease, bone loss and fractures, increased risk of coronary artery disease, hypertension, type 2 diabetes mellitus, and the metabolic syndrome. Further understanding of the pathophysiological link between nephrolithiasis and these systemic disorders is necessary for the development of new therapeutic options.
Collapse
Affiliation(s)
- Khashayar Sakhaee
- Department of Internal Medicine, Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, University of Texas Southwestern Medical Center, Dallas, Texas 75390, USA.
| | | | | |
Collapse
|
3
|
The study of interferences for diagnosing albuminuria by matrix-assisted laser desorption ionization/time-of-flight mass spectrometry. Clin Chim Acta 2012; 413:875-82. [DOI: 10.1016/j.cca.2012.01.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2011] [Revised: 01/25/2012] [Accepted: 01/26/2012] [Indexed: 11/20/2022]
|
4
|
Uric Acid Nephrolithiasis: Basic and Clinical Aspects. Urolithiasis 2012. [DOI: 10.1007/978-1-4471-4387-1_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
5
|
|
6
|
Vega D, Maalouf NM, Sakhaee K. Increased propensity for calcium phosphate kidney stones with topiramate use. Expert Opin Drug Saf 2007; 6:547-57. [PMID: 17877442 DOI: 10.1517/14740338.6.5.547] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Topiramate (TPM) is a neuromodulatory agent that was initially approved as an antiepileptic drug and is increasingly used in the treatment of a number of neurological and metabolic disorders. Among its various pharmacological actions, TPM has been shown to inhibit the activity of specific carbonic anhydrase enzymes in the kidney. This action is associated with the development of metabolic acidosis, hypocitraturia, hypercalciuria and elevated urine pH, leading to an increased risk of kidney stone disease. Despite the cautionary note in the package insert of TPM, the extent of these complications has not been fully explored. Few prescribing physicians are aware of these complications, underscoring the need for improved surveillance. Because the drug is among the most frequently prescribed agents in the US, more controlled studies are required to determine the prevalence of kidney stone disease among TPM users, and the optimal approach to prevent and treat nephrolithiasis in these individuals.
Collapse
Affiliation(s)
- Damaris Vega
- University of Texas Southwestern Medical Center, Department of Internal Medicine and Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, 5323 Harry Hines Boulevard, Dallas, TX 75390-8885, USA
| | | | | |
Collapse
|
7
|
Abstract
Uric acid nephrolithiasis may be the final manifestation of various pathophysiological processes. Recent advances in renal urate transport have elucidated mechanisms by which hyperuricosuria occurs. However, in most uric acid stone formers the primary pathophysiologic defect is an excessively acidic urine pH rather than hyperuricosuria. Insulin resistance may contribute to the development of acidic urine by augmenting endogenous acid production and decreasing renal ammonium excretion. Medical management strategies focus primarily on alkali treatment or decreasing hyperuricosuria.
Collapse
Affiliation(s)
- Mary Ann Cameron
- The Charles and Jane Pak Center for Mineral Metabolism and Clinical Research, The University of Texas Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-8885, USA.
| | | |
Collapse
|
8
|
Welch BJ, Graybeal D, Moe OW, Maalouf NM, Sakhaee K. Biochemical and Stone-Risk Profiles With Topiramate Treatment. Am J Kidney Dis 2006; 48:555-63. [PMID: 16997051 DOI: 10.1053/j.ajkd.2006.07.003] [Citation(s) in RCA: 96] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2006] [Accepted: 07/05/2006] [Indexed: 11/11/2022]
Abstract
BACKGROUND Topiramate is a novel neuromodulatory agent commonly prescribed for the treatment of seizure disorders and for migraine headache prophylaxis. Calcium phosphate kidney stones have been observed with topiramate treatment, but a comprehensive elucidation of stone-risk profile was not reported previously. This study explores the relationship between topiramate treatment and propensity for kidney stone formation. METHODS Thirty-two topiramate-treated subjects and 50 healthy volunteers participated in a cross-sectional study in which serum chemistry test and 24-hour urine collection results were evaluated for stone risk. Furthermore, a short-term longitudinal study was conducted in 7 patients to assess stone risk before and 3 months after topiramate treatment. RESULTS Serum bicarbonate levels were lower with topiramate treatment. Urinary pH, urinary bicarbonate excretion, and fractional excretion of bicarbonate increased, whereas urinary citrate excretion was significantly lower (737 +/- 329 versus 278 +/- 226 mg/d; P < 0.001). Net acid excretion did not change. The relative saturation ratio for brushite increased with topiramate treatment (3.14 +/- 1.69 versus 1.27 +/- 1.26; P < 0.001) because of urinary alkalinization and decreased urinary citrate levels. Urinary saturation of undissociated uric acid decreased (41 +/- 52 versus 76 +/- 60 mg/d; P < 0.001). CONCLUSION Treatment with topiramate causes systemic metabolic acidosis, markedly lower urinary citrate excretion, and increased urinary pH. These changes increase the propensity to form calcium phosphate stones.
Collapse
Affiliation(s)
- Brian J Welch
- Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA
| | | | | | | | | |
Collapse
|
9
|
Abstract
Urinary citrate inhibits calcium stone formation by complexing calcium in a soluble form and by effects on urinary crystals to prevent growth to stones. Low urinary citrate has been recognized for several decades as a contributing factor in some stone forming patients, but recent studies have elucidated the mechanisms and derangements of the renal handling of citrate in various conditions. In addition, oral citrate as an alkalinizing agent can not only increase urinary citrate, but also favorably impact other stone-promoting conditions. This review will focus on the understanding of these concepts.
Collapse
Affiliation(s)
- L Lee Hamm
- Section of Nephrology and Hypertension, Department of Medicine, Tulane University Health Sciences Center, 1430 Tulane Avenue, New Orleans, LA 70112, USA.
| | | |
Collapse
|
10
|
GORDON EE. The metabolism of citrate-C-14 in normal and in fluoroinhibitor-poisoned rats. J Clin Invest 1998; 40:1719-26. [PMID: 13707152 PMCID: PMC290865 DOI: 10.1172/jci104394] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
11
|
|
12
|
CRAWFORD MA, LOUGHRIDGE L, MILNE MD, SCRIBNER BH. Organic acid excretion after calcium gluconate infusions. J Clin Pathol 1998; 12:524-9. [PMID: 13812720 PMCID: PMC479970 DOI: 10.1136/jcp.12.6.524] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
13
|
GORDON EE. Effect of acute metabolic acidosis and alkalosis on acetate and citrate metabolism in the rat. J Clin Invest 1998; 42:137-42. [PMID: 13949194 PMCID: PMC289262 DOI: 10.1172/jci104700] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
|
14
|
CRAWFORD MA. The effects of fluoroacetate, malonate and acid-base balance on the renal disposal of citrate. Biochem J 1998; 88:115-20. [PMID: 14023730 PMCID: PMC1203858 DOI: 10.1042/bj0880115] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
15
|
Pfeiffer N. Dorzolamide: development and clinical application of a topical carbonic anhydrase inhibitor. Surv Ophthalmol 1997; 42:137-51. [PMID: 9381367 DOI: 10.1016/s0039-6257(97)00053-2] [Citation(s) in RCA: 67] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Systemic carbonic anhydrase inhibitors are among the most powerful agents to lower intraocular pressure. Unfortunately, their use is frequently accompanied by undesired side effects. Some are due to the relatively large amounts of drug that have to be systemically administered to inhibit the carbonic anhydrase in the ciliary processes. Recently, dorzolamide, a topical carbonic anhydrase inhibitor, has become commercially available for clinical use. This article reviews the development of topical carbonic anhydrase inhibitors with special reference to dorzolamide. When administered three-times daily, dorzolamide lowers intraocular pressure in a clinically useful manner. Ocular side-effects include frequent stinging and burning and allergy can develop. Systemic side effects have not been observed that could definitively be related to inhibition of extraocular carbonic anhydrase. Blood dyscrasias have not yet been observed. Absence of cardiovascular and pulmonary side effects, as can occur with beta adrenergic antagonists, and lack of pupillary and accommodative stimulation, as occur with cholinergic agonists, might make dorzolamide first-line medical treatment for elevated intraocular pressure.
Collapse
Affiliation(s)
- N Pfeiffer
- Department of Ophthalmology, University Hospital, Mainz, Germany
| |
Collapse
|
16
|
|
17
|
Abstract
Nephrocalcinosis has been reported in patients treated with acetazolamide and other agents, such as furosemide or bicarbonate. We present a case of nephrocalcinosis induced solely by acetazolamide and diagnosed radiographically. Possible mechanisms of pathogenesis are reviewed.
Collapse
Affiliation(s)
- J R Parikh
- Department of Radiology, Kingston General Hospital, Queen's University, Ontario, Canada
| | | |
Collapse
|
18
|
Obialo CI, Clayman RV, Matts JP, Fitch LL, Buchwald H, Gillis M, Hruska KA. Pathogenesis of nephrolithiasis post-partial ileal bypass surgery: case-control study. The POSCH Group. Kidney Int 1991; 39:1249-54. [PMID: 1895677 DOI: 10.1038/ki.1991.158] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Between 1975 and 1983, 838 patients were randomized into the Program on the Surgical Control of Hyperlipidemias (POSCH) trial: 417 to standard medical care and 421 to partial ileal bypass (PIB) surgery. During the course of the trial, an increased incidence of kidney stone formation was found in the surgery group (4%/year) as compared to the control group (0.4%/year). A matched triplet case-control study was conducted to assess the possible causes for the increased incidence of kidney stones. Three groups were studied: PIB stone-formers (S); PIB non-stone formers (N); and non-PIB, non-stone formers in the control group (C). Initially, 162 patients (54 triplets) were selected. Ten percent of the patients declined to participate which resulted in a sample size of 146 patients. The PIB patients had statistically significant (P less than 0.05) lower levels of serum vitamin D metabolites; lower urine volume, pH, citrate, magnesium, carbon dioxide, and sulfate, and higher urinary oxalate, ammonia and relative supersaturation for calcium oxalate and uric acid than the control patients. Although S and N had similar results, those S with no prior history of stones had a higher calcium oxalate supersaturation than similar N with a negative prior history of stones (P less than 0.025). Based on these results, all PIB patients appear to be at risk for kidney stone formation. The combination of reduced urinary volume and calcium oxalate precipitation inhibitor substance with increased calcium oxalate relative supersaturation produced an increase in nephrolithiasis risk in the PIB groups.
Collapse
Affiliation(s)
- C I Obialo
- Renal Division, Jewish Hospital, St. Louis, Missouri
| | | | | | | | | | | | | |
Collapse
|
19
|
Affiliation(s)
- L L Hamm
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri
| |
Collapse
|
20
|
Ahlstrand C, Tiselius HG. Urine composition and stone formation during treatment with acetazolamide. SCANDINAVIAN JOURNAL OF UROLOGY AND NEPHROLOGY 1987; 21:225-8. [PMID: 3433023 DOI: 10.3109/00365598709180326] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Twelve patients who formed renal stones during acetazolamide treatment for glaucoma were studied. Calcium phosphate was the dominating component in the stones. Long term treatment with acetazolamide decreased urinary citrate markedly, which will result in an increased ion-activity product of calcium phosphate and a decreased inhibiting property of urine on calcium phosphate crystallization. The treatment also increased urinary oxalate which together with a low citrate might increase the risk of calcium oxalate crystallization. However, an estimate of the ion-activity product of calcium oxalate in urine (AP [CaOx]-index) was unaffected by the treatment and calcium oxalate was a minor component of the stones.
Collapse
Affiliation(s)
- C Ahlstrand
- Department of Urology, University Hospital, Linköping, Sweden
| | | |
Collapse
|
21
|
François B, Cahen R, Pascal B. Inhibitors of urinary stone formation in 40 recurrent stone formers. BRITISH JOURNAL OF UROLOGY 1986; 58:479-83. [PMID: 3779347 DOI: 10.1111/j.1464-410x.1986.tb05450.x] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The excretion of four inhibitors of urinary stone formation (zinc, magnesium, citrates and glycosaminoglycans (GAG) was studied in 20 normal controls and 40 recurrent calcium stone formers who were placed on a fixed diet restricted in calcium, oxalates and purines. We were unable to show any abnormality in the excretion of Zn, Mg or GAG. In 11 patients, a low level of urinary citrate was a significant feature that was associated in most cases with a urinary pH value above 6. Citrate concentration (per litre) and output (per 24 h) were found to be lower than in the controls in 19 and 33% respectively of the determinations. The overall ratio of average urinary citrate concentration in patients and controls was 0.56, a figure in agreement with previous data.
Collapse
|
22
|
Hörl WH, Echsel E, Hohenegger M. The key role of sex dependency on kidney citrate metabolism in the rat. RESEARCH IN EXPERIMENTAL MEDICINE. ZEITSCHRIFT FUR DIE GESAMTE EXPERIMENTELLE MEDIZIN EINSCHLIESSLICH EXPERIMENTELLER CHIRURGIE 1985; 185:69-75. [PMID: 3969523 DOI: 10.1007/bf01851530] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
An evaluation of the potential role of the kidney in the regulation of the blood citrate level under different acid-base statuses and various diets was performed. Twenty-four hours after bilateral nephrectomy there was a highly significant increase in the blood citrate concentrations in female rats, whereas the blood citrate levels either remained unchanged or decreased in bilateral nephrectomized male animals. Our data clearly indicate a key role of sex dependency on kidney citrate metabolism in the rat.
Collapse
|
23
|
Abstract
Advances in renal lithiasis research have contributed to a better understanding of the many varied factors that contribute to renal calculus formation. Utilizing the newer techniques of ambulatory metabolic evaluation, we can establish a specific diagnosis in 95% of recurrent stone-formers. Since a significant percentage of initial stone-formers will never have a second episode, it is essential to establish the natural history of the patient's stone disease prior to initiating potentially life-long medical therapy. The majority of initial stone-formers can be managed with education concerning modest dietary restrictions and increased fluid intake. For the recurrent stone-former with metabolically active stone disease, it is probably best to design medical therapy to treat the specific urinary chemical abnormality or disease process.
Collapse
|
24
|
Kass MA, Kolker AE, Gordon M, Goldberg I, Gieser DK, Krupin T, Becker B. Acetazolamide and urolithiasis. Ophthalmology 1981; 88:261-5. [PMID: 7231915 DOI: 10.1016/s0161-6420(81)35041-6] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
|
25
|
The Incidence of Nephrocalcinosis and the Urinary Excretion of Citrate and Calcium in Patients with Non-Azotemic type 4 Renal Tubular Acidosis. Urolithiasis 1981. [DOI: 10.1007/978-1-4684-8977-4_120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
26
|
Hargett NA, Ritch R, Mardirossian J, Kass MA, Podos SM. Inadvertent substitution of acetohexamide for acetozolamide. Am J Ophthalmol 1977; 84:580-3. [PMID: 910864 DOI: 10.1016/0002-9394(77)90456-1] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
In three cases acetohexamide (Dymelor), an oral hypoglycemic agent, was mistakenly given to patients instead of acetazolamide (Diamox), which had been prescribed for their glaucoma. A number of similarities, including the fact that both medications are 250-mg white tablets, with similar generic and brand names which are generically repackaged medications juxtaposed on the pharmacist's shelf, predispose to the inadvertent substitution of one medication for the other. In one instance a systemic hypoglycemic reaction resulting in head trauma and confusion ended in an emegency hospital admission following the substitution of acetohexamide for acetazolamide.
Collapse
|
27
|
Abstract
The occurrence of urinary calculi associated with acetazolamide therapy is described. Patients with a history of urinary stones or surgery are a significant risk for further calculus formation when treated with acetazolamide. The concurrent use of sodium bicarbonate further potentiates this risk.
Collapse
|
28
|
|
29
|
|
30
|
|
31
|
Lifshitz F, Harrison HC, Bull EC, Harrison HE. Citrate metabolism and the mechanism of renal calcification induced by magnesium depletion. Metabolism 1967; 16:345-57. [PMID: 6024160 DOI: 10.1016/0026-0495(67)90046-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
32
|
Simpson DP. Regulation of renal citrate metabolism by bicarbonate ion and pH: observations in tissue slices and mitochondria. J Clin Invest 1967; 46:225-38. [PMID: 6018760 PMCID: PMC297041 DOI: 10.1172/jci105525] [Citation(s) in RCA: 73] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The effect of acid-base balance on the oxidation and utilization of citrate and other organic acids has been studied in tissue slices and isolated kidney mitochondria. The results show that: 1) With bicarbonate-buffered media, citrate oxidation and utilization are inhibited in slices of renal cortex and in kidney mitochondria when [HCO(3) (-)] and pH are increased within the physiologic range (pH 7.0 to 7.8; 10 to 60 mumoles HCO(3) (-) per ml). When phosphate or Tris buffers are used, no comparable effect on citrate oxidation occurs when pH is varied. 2) This effect is not demonstrable in heart or liver slices when a physiologic buffer is used. 3) alpha-Ketoglutarate utilization is inhibited in slices of renal cortex under similar conditions. Pyruvate and L-malate utilization are not inhibited in slices or mitochondria. 4) Citrate content in slices of renal cortex incubated with a high [HCO(3) (-)] is considerably greater than the concentration found with a low [HCO(3) (-)] in the medium. This effect is not duplicated by pH change in a nonbicarbonate buffer system. In mitochondria citrate content is also increased markedly at high bicarbonate concentrations. 5) The kinetic characteristics of the inhibition of citrate oxidation are those of a competitive type of inhibition. 6) When pH was varied with a constant [HCO(3) (-)] in the media, citrate oxidation was inhibited by increasing pH in slices of renal cortex but not in mitochondria. On the other hand, when [HCO(3) (-)] was increased without change in pH, no decrease in citrate oxidation occurred in slices, but a marked inhibitory effect was found when mitochondria were used. From a comparison of these results with those previously obtained in intact animal experiments, we conclude that the inhibition of citrate oxidation caused by increasing pH and [HCO(3) (-)] in slices of renal cortex and kidney mitochondria is an in vitro representation of the inhibition of citrate reabsorption in the nephron that occurs in metabolic alkalosis. Thus, citrate clearance increases in metabolic alkalosis because of inhibition of oxidation of reabsorbed citrate within cells of the renal tubules. This inhibition is the result of an inhibitory effect of bicarbonate ion on citrate oxidation in mitochondria.
Collapse
|
33
|
GILL WB, VERMEULEN CW. Causation of stones by 2 co-acting agents--diamox and operative insult upon urinary tract. J Urol 1962; 88:103-9. [PMID: 13898607 DOI: 10.1016/s0022-5347(17)64747-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
|
34
|
|
35
|
|
36
|
|
37
|
CONSTANT MA, BECKER B. The Effect of Carbonic Anhydrase Inhibitors on Urinary Excretion of Citrate by Humans*. Am J Ophthalmol 1960; 49:929-34. [PMID: 13811601 DOI: 10.1016/0002-9394(60)91812-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
38
|
|
39
|
|
40
|
FRICK PG, RUBINI ME, MERONEY WH. Recurrent nephrolithiasis associated with an unusual tubular defect and hyperchloremic acidosis. Am J Med 1958; 25:590-9. [PMID: 13582967 DOI: 10.1016/0002-9343(58)90048-2] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
41
|
OTTO H. �ber den Einfluss des Carboanhydrasehemmstoffes 2-Acetylamino-1,3,4-Thiadiazol-5-Sulfonamid (Acetazolamid) auf die Citronens�ureausscheidung im Harn. ACTA ACUST UNITED AC 1958; 36:633-6. [PMID: 13564739 DOI: 10.1007/bf01480781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
42
|
|