Neonatal treatment with vasopressin antagonist dP[Tyr(Me)2]AVP, but not with vasopressin antagonist d(CH2)5[Tyr(Me)2]AVP, inhibits body and brain development and induces polyuria in the rat

Two vasopressin antagonists, d(CH2)5[Tyr(Me)2]AVP and dP[Tyr(Me)2]AVP, were given to Wistar rats from postnatal day 1 to 21 in order to investigate the influence on development and later diuresis. The latter antagonist significantly reduced body growth from day 3 postnatally onwards. At postnatal day 35 body, total brain, cerebellar and kidney weights were significantly reduced compared with controls. Diuresis, measured at one month of age, was four- to five-fold higher than the control group. Combined treatment with vasopressin failed to abolish the weight disturbances or polyuria. However, animals treated with the vasopressin antagonist d(CH2)5[Tyr(Me)2]AVP did not show developmental or diuretic deficits. Allometric analysis of brain/body relationship of the young animals indicated a disturbance of brain development by dP[Tyr(Me)2]AVP. Although the body and brain growth retardation induced by dP[Tyr(Me)2]AVP supports the hypothesis of a role for vasopressin in brain ontogeny, it can also be the result of a nonAVP-related toxic effect, since it could not be prevented by concomitant treatment with vasopressin.

Involvement of prostaglandin E2, cAMP, and vasopressin in lithium-induced polyuria

The involvement of prostaglandin E2 (PGE2), adenosine 3',5'-cyclic monophosphate (cAMP), and vasopressin in lithium-induced polyuria was investigated in rats. Administration of LiCl (4 mmol/kg body wt) for 7 days induced a marked polyuria with a significant excretion of urinary PGE2. Administration of indomethacin (IND, 5 mg/kg body wt) for 4 days to lithium-induced diabetes insipidus (LiDI) rats diminished urine volume by 80% and urinary PGE2 by 85%. The in vitro data of the intact rat kidney showed that lithium stimulated arginine vasopressin (AVP)-induced PGE2 production and suggested that PGE2 suppressed cAMP synthesis in rat renal medulla. The AVP-induced PGE2 synthesis was greater and the AVP-stimulated cAMP production lower in the LiDI rat kidney in vitro. Interference of the vasopressin-associated cAMP system and the increased PGE2 synthesis in the kidney may be involved in the development of LiDI. The reduced cAMP production in the LiDI rat kidney might be partly due to the increased PGE2 synthesis. In LiDI rats plasma vasopressin increased, whereas AVP concentration in the hypothalamus and the neurohypophysis significantly decreased. It is postulated that lithium stimulates vasopressin release from the central nervous system and that elevated plasma vasopressin potentiates PGE2 production in the kidney synergistically with lithium.

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.

Renal response to vasopressin and indomethacin in cisplatin-treated rats

1. Cisplatin [6 mg/kg body weight, in 0.9% (w/v) NaCl] was injected intraperitoneally as a single dose to two groups of rats (Fischer 344 strain). Two further groups of rats, injected intraperitoneally with an equivalent volume of 0.9% (w/v) NaCl, were used as controls. The cisplatin-treated rats developed a pronounced polyuria which did not recover during an 18 week observation period. 2. After 21 weeks, one group of the cisplatin-treated animals received a 6 h infusion of 2.5% D-glucose. Vasopressin (60 mu-units min-1 100 g-1 body weight) was incorporated into the infusate for the final 2 h. A control group of animals received an identical infusion. One week later the other group of cisplatin-treated rats received a 6 h infusion of 0.9% (w/v) NaCl. Indomethacin was incorporated into the infusate for 15 min, at 3 h 52.5 min, to deliver a dose of 10 mg/kg body weight. A control group again received an identical infusion. 3. Cisplatin did not impair the antidiuretic effect of vasopressin, but it reduced the natriuretic effect of vasopressin, and also impaired the ability of the animals to produce concentrated urine. 4. Cisplatin did not alter basal PGE2 excretion, or the reduction in PGE2 excretion induced by indomethacin. However, the urine flow in the cisplatin-treated group did not fall after indomethacin, whereas there was a fall in urine flow in the control group.

Diabetes insipidus with renal resistance to vasopressin in the desoxycorticosterone-treated dog: a possible role for prostaglandins

We examined the release of vasopressin and the renal response to exogenous vasopressin before and during desoxycorticosterone acetate (DOCA) administration in the dog. As treatment with DOCA produced potassium loss, urine volume increased, urinary osmolality decreased, and urinary PGE2 tended to increase. The increase in urine volume was accompanied by increases in serum sodium, in plasma osmolality and in plasma arginine vasopressin. The threshold for vasopressin release measured during polyuria was higher than control but the rate of vasopressin release was unchanged. The DOCA-induced polyuria was not affected by treatment with vasopressin which further increased plasma vasopressin. Treatment with indomethacin which corrected the increase in urinary PGE2 excretion but not the hypokalemia, restored the renal responsiveness to vasopressin, decreased the secretion of vasopressin, and corrected the polyuria and the hypernatremia. These findings suggest that DOCA-induced polyuria is attributable to a decrease in renal responsiveness to vasopressin which may be mediated in part by an increase in the renal synthesis of prostaglandins.

Indomethacin in streptozocin-induced nephrogenic diabetes insipidus

A 14-year-old female patient with metastatic carcinoid developed streptozocin-induced glomerular, proximal, and distal tubular dysfunction. The latter was in the form of nephrogenic diabetes insipidus, with urine volumes in excess of 11 L/24 h. The prostaglandin synthetase inhibitor, indomethacin, rapidly corrected the polyuria both initially and on rechallenge, independent of change in glomerular filtration rate.

The role of prostaglandins in early polyuria induced by cisplatin in the rat

To assess a possible role of prostaglandins in the early phase of cisplatin-induced abnormalities in renal concentrating ability, three groups of rats were studied. In a first group we measured prostaglandin production from renal medullary microsomes isolated from rats sacrificed at different time periods after cisplatin, 5 mg/kg alone (PB/CP) or cisplatin plus aspirin, 300 mg/kg p.o., 1 h before cisplatin and daily (ASA/CP). In a second group of rats, balance studies were performed in PB/CP and ASA/CP animals for 4 days after cisplatin to determine the effect of such treatment on the renal excretion of solute and water. In another group of rats inulin clearance was measured in PB/CP and ASA/CP animals 4 days after such treatment. The rats received aspirin or phosphate buffer alone (50 mg/ml sodium phosphate, pH 8) to determine the effect of such treatment on prostaglandin production and renal function. In PB/CP Uosm fell and prostaglandin synthesis increased on days 1-3. Prostaglandin synthesis returned to baseline values by day 4, but Uosm remained low. Inulin clearance was low 4 days after cisplatin. In ASA/CP rats prostaglandin synthesis did not increase and the early polyuria was ameliorated. Aspirin did not prevent the later polyuria. Inulin clearance in the ASA/CP group was markedly reduced to levels below those observed with cisplatin alone. These data demonstrate that elevated rates of prostaglandin synthesis occur early in the course of cisplatin-induced renal failure and suggest that prostaglandins may play a role in the early cisplatin-induced concentrating defect.

Treatment of severe lithium-induced polyuria with amiloride

One of the major side effects of lithium is nephrogenic diabetes insipidus. The established treatment for the disorder is thiazide diuretics, which are associated with hypokalemia and reduced lithium excretion, predisposing the patient to lithium toxicity. Amiloride is a new diuretic that reduces lithium-induced polyuria in animals without affecting lithium or potassium levels. The authors found that 10-20 mg/day of amiloride given to eight patients who had become hypokalemic while being treated with hydrochlorothiazide for lithium-induced nephrogenic diabetes insipidus increased renal concentrating ability and reduced polyuria. They conclude that amiloride can be useful in treating lithium-induced nephrogenic diabetes insipidus and merits future randomized clinical trials.

Minimum plasma lithium levels required for effective prophylaxis in DSM III bipolar disorder: a prospective study

Four groups of DSM III bipolar patients, whose plasma lithium levels were maintained at 0.30-0.45 (group A), 0.46-0.60 (group B), 0.61-0.75 (group C), and 0.76-0.90 (group D) mEq/l respectively, were followed-up for two years. The mean number of affective episodes and the mean total morbidity during the lithium treatment period were significantly decreased in all groups except group A when compared with the pre-lithium period. Moreover, in group A, the mean total scores on CPRS depressive and manic items during the interepisodic periods were significantly higher than in each of the other groups. As a result of the low scores of patients in group A and the high scores of patients in group D on the side effect checklist, the frequency and intensity of side effects differed significantly among the four groups. These data suggest that, in the prophylactic treatment of bipolar patients, plasma lithium levels should, as a rule, be adjusted to the range 0.46-0.75 mEq/l.

[Primary polyuric kidney failure and acute yellow liver dystrophy following infusion of glucose substitutes in children]

Four children (aged 2 1/2-14 years) were given infusions of fructose, sorbitol and xylitol after sustaining head trauma (n = 3) or after attempted suicide with carbromal (n = 1). After transitory polyuria renal failure of varying severity set in three to five days after onset of the infusion treatment. Serum osmolality fell to 265-274 mosm/kg, haematocrit to 0.25-0.31, and hyponatraemia developed. Serum creatinine rose to maximally 256-930 mumol/l. Liver damage developed in parallel to the renal failure, two children dying with acute yellow liver atrophy. Two children--given symptomatic treatment with balanced equalization of the hyponatraemia, administration of frusemide and adjusted carbohydrate substitution--were discharged after four to eight weeks with normal renal and hepatic functions. Dialysis was not required. The hepatic and renal abnormalities must have been due to the high amounts of fructose, sorbitol and xylitol, to a total of 7.1-23.0 g/kg on the first day, well above recommended levels.

Monotherapy with nifedipine for essential hypertension in adult blacks

Thirty-two adult Nigerians with mild-to-moderate essential hypertension were included in a double-blind placebo-controlled trial matching nifedipine 20 mg twice daily with placebo for 6 weeks. Nifedipine caused very significant reductions of both systolic and diastolic blood pressures in all patients. Blood pressure fell from a mean of 181.3 (SE 3.9)/114.7 (SE 2.4) to 122.8 (SE 1.9)/79.4 (SE 1.6). Mean arterial pressure fell from a mean of 136.75 (SE -2.2) to 94.19 (SE -1.39). Polyuria was a common side effect in six of the 16 patients who received nifedipine. One additional patient developed transient occipital headache. Nifedipine monotherapy would appear to be an effective first-line drug in the management of essential hypertension in adult blacks.

Medroxyprogesterone acetate induces diabetes insipidus in Chinese hamsters

Injection of a synthetic progesterone, medroxyprogesterone acetate (MPA or Depo-ProveraR), a widely used contraceptive, into Chinese hamsters (Cricetulus griseus) induced a profound polyuria with daily output of dilute urine equal to about 50% body weight of the hamster. However, relatively normal ability for renal urine concentration was demonstrated by administration of exogenous vasopressin. Body weight did not increase during onset of MPA-induced polyuria or during interval of vasopressin-induced oliguria, suggesting that primary polydipsia was not etiologic. Administration of this steroid to Chinese hamsters was nontoxic, although these polyuric animals were unusually sensitive to water deprivation. This polyuria was not observed when progesterone alone was injected into Chinese hamsters or when MPA was given to other related hamster species (Armenian, Syrian, Turkish or Djzungarian). The MPA-injected Chinese hamster represents a unique model of vasopressin sensitive diabetes insipidus induced by a steroid in a species-specific fashion.

Side-effects of lithium at lower therapeutic levels: the significance of thirst

The prevalence of thirst, subjective polyuria and related side-effects was investigated in 87 patients attending a lithium clinic and in a group of 52 controls. Thirst was surprisingly common, occurring in 67% of patients, in spite of the fact that they had been maintained on relatively low levels of lithium, and was due principally to the lithium rather than to other psychotropic drugs. Urine flow and impaired renal water absorption correlated with the serum lithium level and the length of treatment in the patients, despite the fact that few were clinically polyuric. The pattern of the results confirms previous suggestions that lithium may stimulate the thirst mechanism directly as well as via an increased renal resistance to vasopressin. The possible implications in terms of clinical response are discussed.

Serum lithium minimum and diuresis

Serum lithium was analyzed over a 24-hour period in patients who were receiving lithium in one daily dose. Linear regression was performed with urine volume as the independent variable and lithium dose, maximum serum lithium concentration. 12-hour serum lithium, minimum serum lithium, length of treatment, and age of patients as the dependent variables. Only minimum serum lithium and urine volume showed a good positive correlation.

Indomethacin treatment in a patient with lithium-induced polyuria

Lithium intoxication causes polyuria, central nervous system manifestations, and ultimately stupor progressing to coma. Moreover, polyuria leading to hypernatraemia itself can progress to convulsions and coma. We present a patient with lithium intoxication who remained polyuric, hypernatraemic and somnolent despite normal serum lithium concentrations. After institution of indomethacin orally, polyuria and hypernatraemia disappeared and patient regained consciousness.

Amelioration of polyuria by amiloride in patients receiving long-term lithium therapy

Vasopressin-resistant diabetes insipidus is a common side effect of the treatment of affective disorders with lithium. We studied the effect of amiloride on lithium-induced polyuria in nine such patients receiving maintenance lithium therapy who had a vasopressin-resistant defect in urinary concentrating ability. After a mean (+/- S.E.) of 24 +/- 6 days of amiloride administration, the urine volume fell (from 4.7 +/- 0.6 to 3.1 +/- 0.3 liters per 24 hours; P less than 0.005), and the urine osmolality increased (from 228 +/- 35 to 331 +/- 34 mOsm per kilogram of H2O; P less than 0.001). The decrease in urine output was sustained during six months of observation in the absence of any significant change in plasma levels of lithium, potassium, or bicarbonate; urinary excretion of sodium or lithium; or creatinine clearance. Amiloride administration was also associated with a significant increase in urine osmolality (from 575 +/- 54 to 699 +/- 48 mOsm per kilogram of H2O; P less than 0.005) measured after fluid deprivation and the injection of exogenous vasopressin. We conclude that amiloride mitigates lithium-induced polyuria, at least partly, by blunting the inhibitory effect of lithium on water transport in the renal collecting tubule. Thus, amiloride may provide a specific therapy for polyuria in lithium-treated patients while obviating the need for potassium supplementation in the treatment of this kind of polyuria.

Therapeutic experience with lithium in childhood aggressivity

An account is given of the therapeutic experience with lithium in childhood hyperaggressivity. In 13 cases of the hospitalized 17 children between 3 and 12 years of age significant rehabilitation was achieved. Their sociability and ability to adapt themselves to the environment improved to a tolerable level. During treatment, no irreversible side effects were observed. It is recommended that the treatment should be performed either at a child psychiatric unit or by a psychiatrist with adequate experiences in this field and preferably at a hospital.

Respiratory alkalosis and reduced plasmatic concentration of ionized calcium in rats treated with 1,25 dihydroxycholecalciferol

The daily administration of supraphysiological doses of 1,25 dihydroxycholecalciferol (0.1-2.5 micrograms/d/100 g body weight) to rats, produced respiratory alkalosis. With the doses of 0.1-0.2 micrograms/d/100 g and feeding a diet with 0.7% of calcium, calcemias did not exceed 2.75 mM, and significantly reduced plasma ionized calcium levels were measured. The latter phenomenon was found associated with increased urinary excretion of cAMP, soft tissue calcium content, and polyuria with hypostenuria, all known effects of parathyroid hormone. These effects were absent in thyroparathyroidectomized rats treated in the same fashion. Present results suggest that the stimulus of low levels of plasma ionized calcium overcomes the probably inhibitory effect of the steroid on parathyroid hormone secretion.