The Effectof a Cation Exchangeresin on Electrolyte Balanceand Its Use in Edematous Tates

In ancient Greece, "terra sigillata" or "sealed earth" was reputed to be a successful counter agent for poisons (1). Its fame grew through the centuries commensurately with the refined custom of poisoning one's dinner partner. Early trials of the effectiveness of "terra sigillata" are reported in two 16th century documents (2). The first, dated 1580, records that of eight dogs who were fed various poisons, including mercury sublimate, the four that received "terra sigillata" survived, while the others died. A 1581 account details another successful experiment in which the "earth" was administered to a condemned criminal immediately following "a dram and a half of Mercurie Sublimate." "Terra sigillata" was found, in 1914, to consist of oxides of calcium and aluminum with a large proportion of silicates (2). Thompson, the analyst, attributed "its virtues . . . chiefly due to the mystery surrounding its origin and the superstitions connected with its source." In the light of more recent knowledge, however, the action of "terra sigillata" may well be explained on the physico-chemical grounds of an ion exchange. Ion exchangers are insoluble substances which remove ions from solution by releasing one ion in exchange for another (3-6). Way, in 1850, first observed the phenomenon of ion exchange in soil (7). Subsequently a number of naturally occurring substances were found to have cation exchange properties but were of limited use because of their low exchange capacity and chemical instability (8, 9). Advances over the naturally occurring substances were the development of "zeolites" from sodium aluminate and sodium silicate (10-13), and of synthetic organic exchangers from sulfonated coals (14). In 1934, Adams and Holmes prepared synthetic phenol-formaldehyde resins with cation exchange properties and introduced resins prepared from aromatic amines and formaldehyde which were capable of exchanging anions (15). In 1945 anion exchange resins, which remove such ions as chloride, sulfate, and phosphate from solution, were utilized in the therapy of peptic ulcer (16-18). The next year Dock suggested that cation exchange resins, which remove such ions as sodium, potassium, calcium, and magnesium from solution, be used to take up sodium from ingested food. He showed that the particular resin he used was non-toxic in dogs and rats when Fed in massive doses over a two-week period (19). The present study concerns observations of electrolyte interchange between a cation exchange resin and medium, in vitro and in vivo. The resin was also evaluated in the therapy of congestive heart failure and cirrhosis of the liver by comparing measures needed to control accumulation of fluid with and without resin. The resin used was Liquonex CRW 1 passed through a 120 mesh screen. The insoluble cation exchange resin is a sulfonated polystyrene capable of neutralizing from 3.9 to 4.5 mEq. of base per gram of resin.