Kidney compounds

C7H9N402- M.p. 337 C, an alkaloid obtained from cacao seeds or prepared synthetically. Constitutionally it is similar to caffeine, and is also a weak base. It is usually administered as the sodium compound combined with either sodium ethanoate or sodium salicylate, and is employed almost entirely as a diuretic. Physiologically theobromine resembles caffeine, but its effect on the central nervous system is less, while its action on the kidneys, is more pronounced. 

In experimental animals and in vitro, DHBs show a variety of biological effects including binding of metaboHtes to various proteins. Clastogenic effects have been observed in vitro and in some in vivo studies with the three compounds. No reproductive effects have been shown by conventional studies with either hydroquinone, catechol, or resorcinol (122). Hydroquinone has been shown to induce nephrotoxicity and kidney tumors at very high doses in some strains of rat (123) catechol induces glandular stomach tumors at very high dose (124). Repeated dermal appHcation of resorcinol did not induce cancer formation (125). 

Excretion factors are often related to lipophilicity. More lipophilic compounds tend to be excreted by the Hver into the bile, resulting in elimination ultimately in the feces. As this is a relatively slow process, much of the radioactivity having a shorter half-life decays before being eliminated. Polar compounds are more likely to be excreted by the kidneys. 

The kidney is an important organ for the excretion of toxic materials and their metaboHtes, and measurement of these substances in urine may provide a convenient basis for monitoring the exposure of an individual to the parent compound in his or her immediate environment. The Hver has as one of its functions the metaboHsm of foreign compounds some pathways result in detoxification and others in metaboHc activation. Also, the Hver may serve as a route of elimination of toxic materials by excretion in bile. In addition to the Hver (bile) and kidney (urine) as routes of excretion, the lung may act as a route of elimination for volatile compounds. The excretion of materials in sweat, hair, and nails is usually insignificant. 

Although the antibacterial spectmm is similar for many of the sulfas, chemical modifications of the parent molecule have produced compounds with a variety of absorption, metaboHsm, tissue distribution, and excretion characteristics. Administration is typically oral or by injection. When absorbed, they tend to distribute widely in the body, be metabolized by the Hver, and excreted in the urine. Toxic reactions or untoward side effects have been characterized as blood dyscrasias crystal deposition in the kidneys, especially with insufficient urinary output and allergic sensitization. Selection of organisms resistant to the sulfonamides has been observed, but has not been correlated with cross-resistance to other antibiotic families (see Antibacterial AGENTS, synthetic-sulfonamides). 

Antimony compounds have been used to treat leishmaniasis ever since tartar emetic (antimony potassium tartrate) was discovered early in the 20th century to have efficacy against the mucocutaneous form of the disease. The cutaneous form has been treated with tartar emetic formulated in an ointment. Many side effects have been seen with this trivalent antimonial, some of which can be ascribed to the difficulty of obtaining pure antimony for its manufacture. These side effects include toxicity to the heart, Hver, and kidneys. Other promising trivalent antimonials have been abandoned in favor of pentavalent antimonials with lower toxicity. 

The University of Idaho and USFWS, with funds from the Bonneville Power Administration, are also gathering data for registration of erythromycin. Erythromycin is intended for control of bacterial kidney disease in salmonid fingerlings that can also be transmitted by broodstock to the eggs (9). If research is completed on schedule and data indicate that the compound is safe and effective, registration is scheduled for 1994 (see Antibiotics, MACROLIDES). 

Arsenic compounds must be considered extremely poisonous. Dust or fumes irritate mucous membranes and lead to arsenical poisoning. When swallowed they irritate the stomach and affect the heart, Hver, and kidneys. Nervousness, thirst, vomiting, diarrhea, cyanosis, and coUapse are among the symptoms of arsenical poisoning (3). In spite of the toxicity of arsenic compounds, there is evidence that arsenic is an essential nutrient for several animal species (4). 

Toxicity. The toxicity of barium compounds depends on solubility (47—49). The free ion is readily absorbed from the lung and gastrointestinal tract. The mammalian intestinal mucosa is highly permeable to Ba " ions and is involved in the rapid flow of soluble barium salts into the blood. Barium is also deposited in the muscles where it remains for the first 30 h and then is slowly removed from the site (50). Very Httle is retained by the fiver, kidneys, or spleen and practically none by the brain, heart, and hair. 

Three hormones regulate turnover of calcium in the body (22). 1,25-Dihydroxycholecalciferol is a steroid derivative made by the combined action of the skin, Hver, and kidneys, or furnished by dietary factors with vitamin D activity. The apparent action of this compound is to promote the transcription of genes for proteins that faciUtate transport of calcium and phosphate ions through the plasma membrane. Parathormone (PTH) is a polypeptide hormone secreted by the parathyroid gland, in response to a fall in extracellular Ca(Il). It acts on bones and kidneys in concert with 1,25-dihydroxycholecalciferol to stimulate resorption of bone and reabsorption of calcium from the glomerular filtrate. Calcitonin, the third hormone, is a polypeptide secreted by the thyroid gland in response to a rise in blood Ca(Il) concentration. Its production leads to an increase in bone deposition, increased loss of calcium and phosphate in the urine, and inhibition of the synthesis of 1,25-dihydroxycholecalciferol. 

Acebutolol is well absorbed from the GI tract. It undergoes extensive hepatic first-pass metabohsm. BioavailabiUty of the parent compound is about 40%. The principal metaboflte, A/-acetylacebutolol, has antiarrhythmic activity and appears to be more cardioselective. Binding to plasma proteins is only 26%. Peak plasma concentrations of acebutolol are achieved in 2.5 h, 3.5 h for A/-acetylacebutolol. The elimination half-Hves of acebutolol and its metabohte are 3—4 and 8—13 h, respectively. The compounds are excreted by the kidneys (30—40%) and by the Hver into the bile (50—60%). About 40% of the amount excreted in the urine is unchanged acebutolol, the rest as metabofltes (32). 

Sotalol is rapidly and almost completely (>90%) absorbed. Bioavahabhity of absorbed dmg is 89—100%. Peak plasma levels are achieved in 2—4 h. Sotalol is 50% bound to plasma proteins. Plasma half-life of the compound is about 5.2 h. No metabolites of sotalol have been identified indicating littie metabolism. The dmg is excreted mainly by the kidneys (80—90%) and about 10% is eliminated in the feces. The plasma half-life is prolonged in patients having renal failure. Kinetics of the compound are not affected by changes in liver function (1,2). Sotalol has ah the adverse effects of -adrenoceptor blockers including myocardial depression, bradycardia, transient hypotension, and proarrhythmic effects (1,2). 

Carbon tetrachloride is toxic by inhalation of its vapor and oral intake of the Hquid. Inhalation of the vapor constitutes the principal ha2ard. Exposure to excessive levels of vapor is characterized by two types of response an anesthetic effect similar to that caused by compounds such as diethyl ether and chloroform and organic injury to the tissues of certain organs, in particular the Hver and kidneys. This type of injury may not become evident until 1—10 days after exposure. The nature of the effect is deterrnined largely by the vapor concentration but the extent or severity of the effect is deterrnined principaHy by the duration of exposure (38). 

Cadmium and certain compounds Kidney, prostate, lung... 

Lead, because of its history as an air emission, has been fairly mobile and is particularly soluble in acid environments. Silver is used widely in the electronics industry. Intake of silver compounds can result in permanent discoloration of the skin and may result in damage to kidneys, lungs, mucous membranes, and other organs. 

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