Electrolyte excretion

D9. Doe, R. P., Flink, E. B., and Goodsell, M. G., Relationship of diurnal variation in 17-hydroxycortico-steroid levels in blood and urine to eosinophils and electrolyte excretion. J. Clin. Endocrinol. Metab. 16, 196-206 (1956). 

The molecular mechanism of diuretics acting as antihypertensive agents is not completely clear however, use of diuretics causes a significant increase in the amount of water and electrolytes excreted in urine, which leads to a reduction in the volume of extracellular fluid and plasma. This in turn leads to a reduction of cardiac output, which is the main parameter responsible for a drop in arterial blood pressure and venous blood return. Cardiac output is gradually restored, but the hypotensive effect remains, possibly because of the reduced peripheral resistance of vessels. It is also possible that diuretics somehow lower vascular activity of noradrenaline and other factors of pressure in the organism. Methods of synthesizing thiazide diuretics used for hypertension are described in the preceding chapter. Chapter 21. 

Finally, there is an additional increase in electrolyte excretion due to impairment of ascending limb and distal tubule Na+ reabsorption this occurs as a result of lowered tubular Na" concentration and the increased tubular fluid flow rate. 

These are the most efficacious agents available for inducing marked water and electrolyte excretion. The peak diuresis is far greater than that observed maximally with other diuretics. The drugs in this group include furosemide, bumetanide and ethacrynic acid and the main site of action is the thick ascending limb of loop of Henle, thus they are often called loop diuretics. ... 

A summary of the effects of diuretics on urinary electrolyte excretion is shown in Table 15-2. 

The constipating effects of morphine and certain other opioid derivatives have been recognized for some time. These drugs produce a general decrease in GI motility, and they may also reduce fluid loss by increasing the absorption of salt and water or by decreasing fluid and electrolyte excretion from the GI tract.44 The exact manner in which opioids exert these effects, however, is not known. As indicated in Chap-... 

This section discusses the clinical use of diuretic agents in edematous and nonedematous states. The effects of these agents on urinary electrolyte excretion are shown in Table 15-5. 

Eliott C, Newman N, Madan A (2000) Gentamicin effects on urinary electrolyte excretion in healthy subjects. Clin Pharmacol Ther 67 16-21... 

Puschett JB, Goldberg M. The acute effects of furosemide on acid and electrolyte excretion in man. J Lab Clin med 1968 71 666-677. 

Patel VK, Emmett M, Santa Ana C, Fordtran JS. Pathogenesis of nephrocalcinosis after sodium phosphate catharsis to prepare for colonoscopy Intestinal phosphate absorption and its effect on urine mineral and electrolyte excretion. Fluman Pathol 2007 38 193-4. 

Electrolyte excretion pH Comment may be influenced by many factors Kidney weight... 

Fluid and electrolyte imbalance may occur because of rapid administration of large doses or inadequate urinary output, resulting in overexpansion of extracellular fluid. Circulatory overload may produce pulmonary edema or congestive heart failure. Excessive diuresis may produce hypokalemia or hyponatremia. Fluid loss in excess of electrolyte excretion may produce hypernatremia and hyperkalemia. 

Wesson LG, Jr. Electrolyte excretion in relation to diurnal cycles of renal function. Medicine 1964 43 547-92. 

Bile formation occurs by processes that are not hilly defined. It takes place in canaliculi, minute passages lined by specialized modihcations of the hepatocyte membrane, that ultimately unite to form bile ductules. Hepatic bile contains 5% to 15% total solids, the major component of which is bile acids. The increase in biliary water and electrolyte excretion caused by this osmotic effect represents the bile acid-dependent fraction of bile flow. Even with severe depletion of the circulating bile acid pool, as is seen with bile duct diversion, some bile flow continues. The active transport of sodium and of glutathione and bicarbonate is mediated by Na-K-ATPase, which is responsible for the bile acid-independent flow of bile (up to 40% of total flow). Hormones such as secretin increase bile flow by stimulating secretion of sodium, bicarbonate, and chloride. Hormone-dependent flow accounts for 20% to 25% of the total. 

It has been claimed that 5>5 [Pg.65]

INTERSALT Cooperative Research Group. INTERSALT An international study of electrolyte excretion and blood pressure. Results for 24-hour urinary sodium and potassium excretion. BMJ 1988 297 319— 328. 

Hydrogenation of the chlorothiazide molecule led to hydrochlorothiazide, which permitted the dose to be reduced tenfold, but the only practical advantage was that the patient took less drug. This, and various other modifications of the basic compound, led to insignificant changes in electrolyte excretion ratios which were of little practical value clinically. 

In the last ten years, the sulfonamide type of diuretic has yielded spectacularly to intensive study. The recognition that certain sulfonamides could have a useful influence upon renal electrolyte excretion is scarcely 15 years old The basic observations for this diuretic development arose from the sulfa drug era, from observations on the side effects of the first sulfa drug, sulfanilamide. Tishler (62) gives a chart depicting the many new drug fields where valuable... 

In the search for more desirable agents with a more favorable electrolyte excretion pattern, our investigation (59) turned to the aromatic sulfonamides more closely related to sulfanilamide. Emphasis was placed on animal (dog) excretion data rather than in vitro enzyme inhibition results (4). One analog of sulfanilamide, p-carboxybenzenesulfonamide (CBS), a relatively weak car-... 

The mercurials and the carbonic anhydrase inhibitors thus have contributed knowledge concerning two apparently independent renal mechanisms concerned with electrolyte excretion. 

N12. Nordin, B. E. C, The effect of intravenous parathyroid extract on urinary pH bicarbonate and electrolyte excretion. Clin. Sci. 19, 311-319 (1960). 

Kidneys. Prostaglandins produced in the kidneys cause the renal blood vessels to dilate. The greater flow of blood through the kidney results in increased water and electrolyte excretion. 

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