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A study was made of the influence of membrane-active agents with different mechanisms of action (quercetin, amiloride, valinomycin, and digitonin), that modify the transmembrane transfer of inorganic ions, on a modifying effect of a glucose loading in X-irradiated Ehrlich ascites tumor cells. The combination of digitonin with glucose increased the damaging effect of radiation on tumor cells by 1.8-2.2 times as compared to glucose alone. Merely insignificant changes in the radiation-modifying effect of glucose were observed when it was combined with other membrane-active agents.

Hydrochlorothiazide (HCT), 25 or 50 mg a day, alone and in combination with triamterene (T), 50 and 100 mg, respectively, or amiloride (A), 2.5 and 5 mg, respectively, was examined for effects on daily urinary potassium and sodium excretion. Daily sodium excretion was increased 1.5-2-fold with a double dose of the combined drugs as compared with their single dose. T and A produced additive effects on the natriuretic action of HCT. Lower doses of HCT and T failed to prevent urinary potassium loss, but their potassium-sparing effect was shown with their double dose. This effect was largely displayed by A given in a single or double dose. Lower serum potassium levels were seen with all the drugs, but this was less marked with HCT combined with T or A than with HCT monotherapy. Their double dose reduced serum potassium levels to an insignificantly greater extent. In some cases, the elderly patients developed hyperkalemia during the combined therapy. Thus, with the routine dose ratios, A showed a slightly higher potassium-sparing effect than did T. Some patients taking HCT in combination with T showed reddish-brown crystals and casts in the urinary sediment, which may indicate its tubular interstitial damaging action. Consequently, use of the combined drugs is more preferable than HCT monotherapy, and HCT in combination with A is likely to be more preferable than that with T.

A comparative study was undertaken to examine antihypertensive effects and impact of hydrochlorothiazide (HCT) alone or in combination with triamterene or amiloride on the hemodynamics of 79 patients with Stage II hypertension. With small doses, the resting recumbent systolic blood pressure was decreased to a significantly greater extent when the combinations (HCT + triamterene, in particular HCT + amiloride) were used than when the agent alone was given; diastolic blood pressure became lower only with a combination of HCT + amiloride than its monotherapy. When double doses were used, no potentiating antihypertensive action of potassium-sparing diuretics was ascertained. It was concluded that it was more preferable to use HCT in combination with diuretics, amiloride in particular, than as monotherapy.

The clinical pharmacology of the diuretic amyloride was studied in 60 patients suffering from circulatory insufficiency of various origin. Midamor and moduretic of the "Merck" firm (USA) were used in a dose of 1 to 4 tablets. The duration of treatment was from 3 days to 18 months. It was found that under the effect of amyloride natriuresis increases moderately in patients with circulatory insufficiency with no simultaneous increase in the loss of potassium with the urine. As the circulatory insufficiency becomes more severe, the natriuretic and potassium-saving effect of the drug diminishes. Amyloride potentiates the diuretic and natriuretic effect of furosemide and hydrochlorothiazide well without increasing kaliuresis. In patients in whom the disease is less severe, two-week treatment with amyloride leads to an authentic increase in the total metabolic potassium in the organism. The patients tolerate the drug well. It is recommended for wide clinical use.

In 75 patients with circulatory insufficiency of various degree the diuretic effect of moduretic was studied. In 25 of them besides the potassium and sodium metabolism and in 33 others, with a background of chronic ischemic disease of the heart and hypertensive disease, the state of the hemocoagulation system was investigated in the moduretic medication. In 24 patients with hypertensive disease of the I--IIA stage subject to study was the effect of moduretic on the arterial pressure, with this drug administered by mouth in doses of 3 to 1/2 tablet a day. The drug proved to have a marked duretic effect in patients with different degree of circulatory insufficiency. It increases sodium excretion with urine and retains potassium in the organism, without causing hyperkaliemia. In patients with circulatory insufficiency of the I degree the drug can provoke thrombogenesis and in cases of the IIA, IIB and III degree may be considered a drug of choice. Moduretic brings down the systolic and diastolic pressure in patients with hypertensive disease of the I and II stages.