Renal excretion of cation in the dog during infusion of isotonic solutions of lithium chloride

Edward Trautner (1890-1978), a pioneer of psychopharmacology

This article examines the scientific career of Edward Trautner, who did pioneering research in the 1950s on lithium treatment for psychiatric disorders. Trautner was the first scientist to study the mechanism of action of lithium as a psychiatric medication. His research established that lithium could be used safely and rationally, and anticipated by a decade the large volume of research in the 1960s and 1970s that led to international acceptance of lithium treatment for mood disorders. Trautner was a pioneer of biological psychiatry who considered pharmacology to be a useful therapeutical tool rather than a permanent cure for putative chemical imbalances. His research involved cross-disciplinary collaborations that combined clinical and laboratory research in the disciplines of psychiatry, physiology, biochemistry, teratology, and even oncology. Trautner himself had a multidisciplinary background that included publications in literature and philosophy.

The association between lithium in drinking water and neuropsychiatric outcomes: A systematic review and meta-analysis from across 2678 regions containing 113 million people

BACKGROUND

Lithium in drinking water may have significant mental health benefits. We investigated the evidence on the association between lithium concentrations in drinking water and their neuropsychiatric outcomes.

METHODS

We conducted a systematic review and meta-analysis and searched Pubmed, Embase, Web of Science, PsycINFO and CINAHL up to 19 January 2020, for peer-reviewed research examining the association between lithium concentrations in drinking water and neuropsychiatric outcomes. We used a pairwise analysis and a random effects model to meta-analyse suicide rates and psychiatric hospital admissions. We assessed for publication bias using Egger's test and Duval and Tweedie's Trim and Fill analysis.

RESULTS

Twenty-seven studies including 113 million subjects were included in this systematic review. Meta-analysis of 14 studies including 94 million people found higher lithium concentrations were associated with reduced suicide rates (r = -0.191, 95% confidence interval = [-0.287, -0.090], p < 0.001) and meta-analysis of two studies including 5 million people found higher lithium concentrations were associated with fewer hospital admissions (r = -0.413, 95% confidence interval = [-0.689, -0.031], p = 0.035). We found significant heterogeneity between studies (Q = 67.4, p < 0.001, I² = 80.7%) and the presence of publication bias (Egger's test; t value = 2.90, p = 0.013). Other included studies did not provide sufficient data to analyse other neuropsychiatric outcomes quantitatively.

CONCLUSION

Higher lithium concentrations in drinking water may be associated with reduced suicide rates and inpatient psychiatric admissions. The relationship with other neuropsychiatric outcomes and complications remains unclear. Further research is required before any public health recommendations can be made.Trial registration number: The study was registered with PROSPERO, number CRD42018090145.

Lithium dilution cardiac output measurements using a peripheral injection site comparison with central injection technique and thermodilution

OBJECTIVE

The lithium dilution technique for the measurement of cardiac output by the central injection of lithium chloride was introduced by Linton et al. in 1993. In the present report, we compare lithium dilution cardiac output measurement (LD) by the peripheral injection of lithium chloride (pLD) and by central venous injection (cLD), cardiac output determined by electromagnetic flowmetry (EM), and conventional thermodilution cardiac output measurement (TD) on ten swine.

METHODS

The animals were monitored with a pulmonary artery catheter, a femoral artery catheter, and an electromagnetic flowmeter placed around the ascending aorta. cLD, pLD, TD, and EM were determined at the baseline, then in a hyperdynamic state produced by dobutamine administration, at a second baseline, and finally in a hypodynamic state induced by propranolol during deep anesthesia. Data were analyzed by linear regression analysis and the comparison method described by Bland and Altman; bias and precision were calculated using the method of Sheiner and Beal.

RESULTS

The correlation coefficient between pLD and EM (0.86) was significantly less than that between cLD and EM (0.96), however it was not significantly different from that between TD and EM (0.85). The precision value of pLD (0.14) was the same as that of TD (0.14).

CONCLUSION

The results of the present study indicate that pLD is a reliable technique.

Binding of lithium and boron to human plasma proteins

The binding of lithium and boron, at normal physiological levels, to plasma proteins has been investigated by the techniques of precipitation with ethyl alcohol and gel chromatography. Assays of lithium and boron were made by thermal neutron activation and mass spectrometric assay of 3He and 4He. Results of alcohol precipitation experiments for plasma from two apparently healthy donors showed that 13+/-4% and 16+/-3% of the lithium in plasma is protein bound, but essentially no boron is bound under the conditions used. We believe that because of denaturation of proteins which occurs during alcohol precipitation, these percentages represent lithium and boron tightly bound to protein molecules. The results of the gel-chromatography experiment, on the other hand, showed that lithium and boron are bound to a wide range of plasma proteins, from low (approximately 60,000 amu) to high (approximately 1,000,000 amu) molecular weights, and to very low- (approximately 6000 amu) molecular-weight ligands. Although a clear identification of the specific proteins which bind lithium and boron cannot be made at present, some possibilities can be suggested.

Chronopharmacokinetics and chronotoxicity of lithium in mice eating normal and low-sodium diets

The temporal aspects of the pharmacokinetics and toxicity of lithium were studied in mice eating normal and low-sodium diets. ICR male mice, housed under a light:dark (LD; 12:12) cycle, were injected with variable doses of lithium chloride i.p. A circadian rhythm was found in lithium clearance after a single administration in mice eating the normal diet showed the maximum value in the early dark phase and the minimum in the early light phase. The repeated administration of lithium did not affect the rhythm of the pharmacokinetics of the drug under the LD cycle. Although the low-sodium diet significantly decreased the lithium clearance, it did not influence the rhythm of the clearance. Higher toxicity was demonstrated in mice injected with the drug at the time of day with lower lithium clearance in the single-dose study but not in the repeated-doses study, regardless of the diet conditions. The low-sodium diet increased the acute and chronic toxicity of lithium. The results indicate that there is a circadian rhythm of acute toxicity and clearance of lithium after a single dose or repeated administration of the drug in mice eating normal and low-sodium diets and that the low-sodium diet increases lithium toxicity by reducing the clearance of the drug without influencing the rhythm characteristics.

Renal handling of endogenous lithium in experimental diabetes mellitus in the rat

1. The usefulness of determining the renal handling of endogenous lithium as a marker of proximal tubular sodium reabsorption was assessed in streptozotocin induced diabetes mellitus in the Sprague-Dawley rat. 2. The clearance and fractional excretion of lithium were determined before and following the development of diabetes mellitus, and compared with measurements of proximal tubular reabsorption made directly using micropuncture techniques. Endogenous lithium was measured in order to avoid the toxic tubular effects of exogenously administered lithium salts. 3. Although a trend existed for a reduction in the fractional excretion of lithium in diabetic animals (1.8 +/- 0.3 vs 2.4 +/- 0.5%; P greater than 0.20), this did not reach statistical significance and did not accurately reflect the change in directly measured tubular Na reabsorption. 4. The decrease in proximal tubular Na reabsorption demonstrated in diabetic animals treated with phlorizin was not significantly reflected in the fractional lithium excretion, although again a corresponding trend was evident (1.9 +/- 0.8 vs 0.6 +/- 0.2%; P greater than 0.10. 5. In summary, the significant alterations in tubular Na handling in diabetes mellitus, previously demonstrated directly using micropuncture techniques, are not reflected in the renal handling of endogenous lithium. This indirect method is inadequate to assess proximal tubular Na transport in experimental diabetes mellitus.

Evaluation of lithium clearance as a marker of proximal tubule sodium handling

Estimations of proximal tubule sodium reabsorption with the FELi method come closer to direct measurements than any other indirect method. There is little doubt that most lithium reabsorption takes place in the proximal tubules, very likely in proportion to the reabsorption of sodium and water. It is also likely that changes in proximal tubule sodium reabsorption due to changes in volume status are paralleled by changes in proximal tubule lithium reabsorption, at least in the superficial nephrons. Nonetheless, changes in FELi probably do not purely reflect changes in proximal reabsorption, since lithium is also handled beyond the proximal tubules. Acknowledged problems are lithium reabsorption in Henle's loop and in the late distal and collecting tubules. The latter occurs in the rat and the dog, but not or much less in men. Sodium restriction enhances this lithium transport considerably. It is as yet uncertain whether other conditions, such as increased vasopressin activity or lowering of renal perfusion pressure, also influence this transport. Amiloride appears to prevent this reabsorption of lithium. Therefore, this drug can be used in lithium clearance studies whenever unwanted "distal" lithium reabsorption is expected. Lithium reabsorption in Henle's loop forms a greater problem as it cannot be prevented by any drug without influencing proximal tubule reabsorption. It is estimated that about 7% of the filtered lithium (one-tenth of total lithium reabsorption) is normally taken up here, preferentially in deep nephrons. In view of studies with furosemide, this reabsorption probably varies with sodium intake, but the proportion of this variation to that of proximal tubule lithium reabsorption is obscure. This remains an uncertain factor in any circumstance where the lithium clearance method is used. In some conditions the change in FELi may be so large relative to the expected changes in proximal reabsorption, that use of FELi as marker of end-proximal solute delivery seems unjustified. Disproportionately large suppression is likely during mineralo-corticoid-induced volume expansion, and stimulation during prostaglandin synthesis inhibition and vasopressin. Based on observations in these conditions the potential range of lithium reabsorption in the loop of Henle would be 0 to 15% of filtered load. In this review attention was paid mainly to the validity of lithium clearance as a pure "proximal marker". Many of our interpretations suffer from incomplete certainty with respect to the renal effects of tested maneuvers, a problem which is acknowledged.(ABSTRACT TRUNCATED AT 400 WORDS)

Prevalence, pathogenesis, and treatment of renal dysfunction associated with chronic lithium therapy

From the analysis of several studies published from 1979 to 1986 comprising 1,172 patients, we estimated that glomerular filtration rate (GFR) was normal in 85% of unselected patients on chronic lithium therapy. The remaining 15% of patients displayed only mild reduction in GFR, clustering at approximately 60 mL/min. Thus, the data available to date do not support earlier concerns that long-term lithium therapy could eventuate into renal insufficiency. The most prevalent renal effect of lithium is impairment of concentrating ability, which we estimated to be present in at least 54% of 1,105 unselected patients on chronic lithium therapy. This defect translated into overt polyuria in only 19% of unselected cases. A renal lesion confined to the collecting tubule has been described in humans who have taken lithium for short periods of time. This lesion may represent the collecting tubule's response to the intracellular accumulation of lithium, which interferes with cAMP formation and results in an early and probably reversible inhibition of antidiuretic hormone (ADH)-mediated water transport. However, long-term lithium therapy may induce a progressive and partly irreversible defect in concentrating ability. The potential risk for dehydration associated with lithium-induced polyuria, as well as the discomfort inherent to this side effect, deserves evaluation and consideration for therapeutic intervention. Amiloride has additional advantages over conventional treatment of nephrogenic diabetes insipidus using thiazide diuretics. The action of amiloride on ADH-mediated water transport seems specific in as much as it is capable of preventing the uptake of lithium in high resistance epithelia and thereby prevents the inhibitory effect of intracellular lithium on water transport. Unlike thiazides, amiloride has a weak natriuretic effect and is less likely to increase plasma lithium levels by causing volume contraction. In addition, amiloride, by conserving potassium, obviates the need for potassium supplementation that is usually required to prevent hypokalemia when thiazides are used to treat lithium-induced polyuria. Since amiloride may prevent chronic intracellular lithium accumulation in the collecting tubule, future studies should elucidate whether amiloride also has a role in preventing lithium-induced chronic tubulo-interstitial damage.

Glomerular filtration rate and PCO2 as determinants of lithium reabsorption

To examine whether lithium reabsorption varies in proportion to the bicarbonate-dependent reabsorption of water and chloride, reabsorption was altered by varying PCO2 and glomerular filtration rate (GFR) in volume-expanded, anesthetized dogs during ethacrynic acid infusion. At constant GFR and plasma bicarbonate concentration, lithium, bicarbonate, chloride and water reabsorption were inversely related to plasma pH during variations in PCO2. Lithium and bicarbonate reabsorption varied by 9 +/- 1% and chloride reabsorption by 7 +/- 1% as plasma pH was altered by 0.1 unit from plasma pH 7.5. Calculation of reabsorbate concentrations indicated that lithium was reabsorbed as readily as water (reflection coefficient = 0). During mechanical constriction of the suprarenal aorta, GFR was reduced at constant plasma pH. Bicarbonate reabsorption fell more than chloride, water and lithium reabsorption. Lithium reabsorption was not significantly reduced until GFR was reduced by 35%. In stop-flow studies during ouabain infusion, urinary lithium concentrations were reduced below plasma concentrations. This is compatible with passive diffusion of lithium along a lumen-positive potential exceeding 10 mV in the diluting segment. Thus, lithium reabsorption behaved as expected for bicarbonate-dependent paracellular reabsorption during variations in PCO2; when GFR is reduced, an additional component of lithium reabsorption is disclosed.

Evidence for bicarbonate-dependent lithium reabsorption in dog kidneys

To examine whether lithium is reabsorbed along a transcellular or a paracellular route, experiments were performed in anesthetized volume-expanded dogs under conditions of constant glomerular filtration rate (GFR). Quabain, in doses inhibiting about 80% of Na, K-ATPase, and ethacrynic acid, another inhibitor of transcellular NaCl reabsorption, did not inhibit lithium or bicarbonate reabsorption. Lithium reabsorption increased in proportion to plasma concentration of lithium (PLi) up to 12 mM, suggesting a passive transport of lithium. During ouabain administration acetazolamide halved bicarbonate reabsorption, the main driving force for paracellular reabsorption, and halved the reabsorption of lithium. The reabsorbate concentration of lithium, calculated from data obtained before and after acetazolamide infusion, was almost equal to PLi. Mannitol, which reduces paracellular osmotic transport without affecting bicarbonate reabsorption, reduced lithium and chloride reabsorption in the same proportion as acetazolamide (r = 0.87). Combined acetazolamide and mannitol administration reduced fractional lithium reabsorption to 0.09 +/- 0.02. These data indicate that lithium is not actively transported but reabsorbed passively along a paracellular route by osmotic forces provided by transcellular NaHCO3 reabsorption.

Lithium concentration in the muscle compartment of manic-depressive patients during lithium therapy

Pharmacokinetic (PK) techniques were used to study the effect of lithium (Li+) on Li+ fluxes and concentrations in body compartments of manic-depressives. Patients not yet on Li+ therapy were similar to normal controls in all parameters. Comparison of patients before and during chronic Li+ therapy showed no effect of Li+ therapy on intestinal absorption and renal excretion of Li+. The calculated erythrocyte (RBC)-to-plasma Li+ concentration ratio increased with Li+ therapy, as already known from direct measurements. The calculated muscle-to-plasma Li+ concentration ratio was 6-8 times higher than the RBC ratio, and increased from 1.8 to 4.2 with Li+ therapy. The higher Li+ concentration in human muscle compared to RBC is attributed to muscle's higher inside-negative resting potential, and may underlie side effects that arise in muscle from Li+ therapy. The discrepancy between the observed muscle-to-plasma ratio and that predicted for a passively distributed ion is attributed to extrusion by a countertransport process, and the increase in the observed ratio with Li+ therapy is attributed to inhibition of countertransport, as already established for RBC. Since muscle resembles nerve as an excitable cell, muscle Li+ warrants evaluation as a predictor of therapeutic response and side effects during Li+ therapy.

Lithium pharmacokinetics: single-dose experiments and analysis using a physiological model

The kinetics of lithium (Li+) distribution after a single dose was studied in healthy human subjects. Experiments were performed by simultaneously following changes of Li+ concentration in plasma, erythrocytes (RBC), and urine. The data were fitted by a simple but physiologically realistic model, so that extracted rate constants could be assigned to real body compartments and compared with independent measurements of cellular transport characteristics. The extracted rate constants were used to calculate steady-state cell-to-plasma Li+ ratios for RBC and for inaccessible cells (mainly muscle). In both cell types, the intracellular Li+ concentration is far below electrochemical equilibrium. This finding suggests that the Li+ countertransport efflux mechanism of RBC may be shared with muscle. We also present evidence for a circadian rhythm in Li+ excretion that parallels the daily cycle of Na+ and K+ excretion.

A micropuncture study of the renal handling of lithium

Although clearance studies in man and experimental animals indicate that filtered lithium is reabsorbed primarily in the proximal tubule, it is unclear whether lithium is also reabsorbed in distal portions of the nephron. Micropuncture studies were, therefore, performed to determine the nephron sites involved in lithium transport during free flow. A method was established to estimate the concentration of lithium in nanoliter samples, using the Helium Glow photometer, which permitted the accurate measurement of lithium in tubular fluid samples over a range from 0.5--30.0 mM. Approximately 56% of filtered lithium and tubular fluid was reabsorbed at the end of the proximal convolution, while at the early distal tubule 75% of filtered lithium and water was reabsorbed. There was no change in net transepithelial movement of lithium beyond the loop of Henle. These data suggest that lithium transport is localized to the proximal tubule, including the pars recta. Lithium reabsorption does not occur in distal tubule or collecting duct. Beyond the early distal tubule net movement of lithium and sodium is dissociated.

Micropuncture study on the effects of lithium on proximal and distal tubule function in the rat kidney

Micropuncture studies were performed in rats infused with LiCl to induce stable plasma lithium concentrations of 2--3 mEq/l, or with an equivalent amount of NaCl. In free flow experiments LiCl reduced proximal tubule fractional reabsorption of sodium and potassium. Reduced reabsorption of bicarbonate, as reflected by a decrease in TF/PCl, was also observed. Proximal fractional reabsorption of chloride, however, was not affected. The TF/PIn at the end proximal tubule was 2.6 +/- 0.2 (mean +/- SEM) in controls and 2.1 +/- 0.1 in the experimental animals (P less than 0.025). In the distal portions of the nephron lithium treatment caused a fall in fractional reabsorption of water and sodium, while potassium secretion was stimulated in the distal tubule. Previous studies have indicated that lithium influences antidiuretic hormone stimulated water transport in the collecting duct. These experiments demonstrate that lithium also affects the transport of water and electrolytes in multiple nephron segments, including the proximal and distal convolution.

Activation of tubulo-glomerular feedback by chloride transport

To define the luminal agent(s) responsible for the reduction of nephron filtration rate following increases of loop of Henle flow rate early proximal flow rate (EPFR) during loop perfusion with 17 different salt solutions were compared to the non-perfused tubules. During orthograde microperfusions a reduction of EPFR as indication of a feedback response was noted with a number of monovalent Cl- and Br- salts (LiCl, KCl, NaCl, RbCl, CsCl, NH4Cl, choline Cl, NaBr, KBr), with Na+ salts except Na acetate (NaHCO3, NaNO3, NaF, NaI, NaSCN), and with CaCl2 and MgCl2. These latter 2 solutions where used in a concentration of 70 mM while all other solutions had a concentration of 140 mM. During retrograde perfusion from the distal to the proximal end of the loop of Henle EPFR fell significantly with Cl- and Br- salts with percentage changes of EPFR ranging from -8.0 to -44.3%. In contrast, Cl- free salts and Cl- salts of divalent cations were associated with percentage changes of EPFR ranging from +7.1 to -6.2%, significance being reached only during perfusion with NaSCN. When furosemide (5 x 10(-4) M) was added to NaBr or KBr a feedback response was not observed. During orthograde perfusion with NaNO3 distal Cl- concentrations were 44.2 +/- 5.08, mM (mean +/- S.E.) at a perfusion rate of 10 nl/min and 59.1 +/- 3.93 mM at a rate of 40 nl/min. CaCl2 perfusion induced a marked elevation of distal Cl- concentrations to levels higher than 140 mM. Loop chloride handling was normal during RbCl perfusion. The magnitude of the feedback response during retrograde perfusion was not changed by lowering NaCl concentration from 140 to 60 mM, but fell when NaCl concentration was further reduced. In contrast to orthograde perfusions it was insensitive to changes in flow rate. Our results are compatible with the thesis that feedback responses depend critically upon the rate of Cl- transport probably across the macula densa cells. Br- ions can replace Cl- because they appear to share a common transport pathway which can be inhibited with furosemide. Unspecificity of feedback responses during orthograde microperfusions is due to presence of Cl- ions in the macula densa region even when solutions are initially Cl- free. Cl- salts of divalent cations do not elicit a feedback response because Cl- transport is severely curtailed.

"Antidotal thirst": a response to intoxication

Albino rats increased their intake of water soon after they were given a load of 0.12 molar lithium chloride in the stomach. Alterations in blood volume and tonicity could not account for the magnitude of the thirst observed, which served to facilitate the renal excretion of the toxic lithium ions.

Salivary excretion of lithium. II. Functional analysis

Salivary Li+ was actively secreted by the cat submaxillary gland, inversely to the rate of flow, at concentrations above serum level. Stop-flow studies indicated ductal secretion of Li+ by a HgCl2 and ouabain-sensitive mechanism. Salivary secretion of Li+ did not resemble Na+ but was similiar to K+ secretion.

The effect of lithium on the electrocardiogram of animals and relation of this effect to the ratio to the intracellular and extracellular concentrations of potassium

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