Sodium avidity

Most patients with large ascites also retain sodium avidly and may become hyponatremic if there is a decrease in free water excretion. Untreated, this can lead to a decrease in renal function and the hepatorenal syndrome.4,13... 

Acute renal toxicity may occur within days of initiating therapy. Serum creatinine concentration rises and creatinine clearance decreases. Hypertension, hyperkalemia, sodium avidity, and hypomagnesemia may occur. No urine sediment abnormalities are seen. Urinary enzyme excretions increase, but are not reliable indicators of toxicity. Renal biopsy reveals thickening of arterioles, mild focal glomerular sclerosis, proximal tubular epithelial cell vacuolization and atrophy, and interstitial fibrosis. Biopsy is useful to distinguish acute cyclosporine nephrotoxicity from renal allograft rejection, the latter being evidenced by cellular infiltration. ... 

Avermectin (Avid ) is a prodnct nsed in commercial crop production. The chemical is produced by bacteria and is used to control leafminers and spider mites. Sodium aluminofluoride or cryolite (Kryocide ) has been used for many years in organic crop production. This product is used to control several types of insects on a wide variety of crops. 

Osmotic diuretics are used to increase water excretion in preference to sodium excretion. This effect can be useful when avid Na + retention limits the response to conventional agents. It can be used to maintain urine volume and to prevent anuria that might otherwise result from presentation of large pigment loads to the kidney (eg, from hemolysis or rhabdomyolysis). Some oliguric patients do not respond to osmotic diuretics. Therefore, a test dose of mannitol (12.5 g intravenously) should be given before starting... 

The chemical properties o orthophosphoric add.—W. Muller-Erzbach21 has discussed the affinity of the metals for phosphoric acid. J. Thomsen found the avidity of a mol. of phosphoric acid for one of sodium hydroxide to be a quarter of the value of that for hydrochloric acid. The affinity of phosphoric acid for the bases is greater than that of carbonic acid, boric acid, phosphorous acid, and hypophosphorous acid. The catalytic action of phosphoric acid on the reaction between bromic and hydriodic acids has been studied by W. Ostwald on the reaction between iodic and sulphurous acids, by R. Hopke and A. Purgotti and L. Zanichelli on hydrazine sulphate, N2H4.H2S04. According to W. Ostwald, the velocity constant for the inversion of cane sugar by phosphoric acid is 6-21 when the value for hydrochloric acid is 100 and J. Spohr showed that the presence of neutral salts at 25° retards, or at 40° completely suppresses,the activity of phosphoric acid. 

Based on the avidity of cobalt for cyanide ions, intravenous injection of the cobalt EDT A complex has been recommended as being the best antidote in cyanide poisoning73). Earlier therapy was based on sodium nitrite and sodium thiosulphate, with partial conversion of haemoglobin to methaemoglobin. 

Hazards Do not store 30% sodium azide solution for prolonged periods of time. Extinguish all flames before using ethyl acetate and hexanes, and avid inhalation of vapors. Wear gloves when handling acetyl chloride, which is corrosive, and avoid inhalation of vapors. 

Like the acetylcholine receptor channel, the sodium channel also was purified on the basis of its ability to bind a specific neurotoxin. Tetrodotoxin, an organic compound isolated from the puffer fish, binds to sodium channels with great avidity (K nM). The lethal dose of this poison for an adult human being is about 10 ng. The sodium channel was first purified from the electric organ of electric eel, which is a rich source of the protein forming this channel. The isolated protein is a single chain of 260 kd. 

Dudley, F.X, Kanel, G.C., Wood, L.X, Reynolds, T.B. Hepatorenal syndrome without avid sodium retention. Hepatology 1986 6 248 - 251... 

Hepatorenal syndrome, functional renal failure in the setting of cirrhosis in the absence of intrinsic renal disease, occurs in patients with cirrhosis as a result of intense vasoconstriction within the renal cortical vasculature. It is common and develops in approximately 40% of patients with cirrhosis and ascites within 5 years. The resultant reduction in blood supply to the kidneys causes avid sodium retention and oliguria. The vasoconstriction that occurs in the kidneys is in stark contrast to the state of systemic vasodilation that is characteristic of chronic liver failure. The pathophysiologic mechanism responsible for these effects is unknown, but is linked to the systemic vasodilation, hypovolemia, and hyperkinetic circulation seen in chronic liver failure. ... 

Patients with hypovolemic hypotonic hyponatremia, on the other hand, should be treated with normal saline because the concentration of osmotically effective urine cations is invariably less than that of isotonic saline. In contrast to patients with SIADH, sodium is avidly reabsorbed throughout the nephron when the effective circulating blood volume is decreased. Thus the urine osmolality is primarily comprised of urea, and the concentration of urine sodium is often less than 20 ruEq/L. 

---