RENAL EXCRETION AND DISTRIBUTION OF CEFTIZOXIME IN RATS

  • 1 January 1981
    • journal article
    • research article
    • Vol. 217  (1) , 209-214
Abstract
A clearance method for ceftizoxime (CZX), a new cephalosporin antibiotic, was designed and utilized to assess the mechanism of renal excretion and evaluate kidney distribution under steady-state serum level. Renal clearance ratio of CZX to inulin, when corrected for protein binding, was 1.6 at a serum level of 13 .mu.g/ml and was decreased to around unity with a serum level of 700 .mu.g/ml or higher or by infusing p-aminohippuric acid or probenecid. The clearance ratio appeared to be independent of urinary pH or changes in urinary flow. The kidney/serum concentration ratio for CZX decreased from 2.5-1.5 in proportion to the extent of reduction of the clearance ratio. p-Aminohippuric acid and probenecid further reduced the kidney/serum ratio to about 1.0 with concomitant inhibition of tubular transport of CZX. Cortex/serum and medulla/serum ratios were also reduced similarly to that of the whole kidney. The tubular transport of CZX is similar to that for the p-aminohippuric acid transport system and passive reabsorption from the tubular lumen may not necessarily be present.