cefsulodin and desacetylcefotaxime

Topics: Anti-Bacterial Agents; beta-Lactams; Cefmenoxime; Cefmetazole; Cefoperazone; Cefotaxime; Cefotiam; Cefsulodin; Ceftazidime; Ceftizoxime; Ceftriaxone; Cephalosporins; Cephamycins; Drug Interactions; Drug Resistance, Microbial; Enterobacteriaceae; Enterobacteriaceae Infections; Humans; Imipenem; Moxalactam

Closely related methods for the determination of several cephalosporins in plasma and urine are described. Deproteinized plasma or diluted urine is directly injected on a RP-8 or RP-18 bonded-material column. Chromatography is performed either in the reversed-phase or the ion-pair mode. The limits of sensitivity range from 0.4 to 2 mumol of cephalosporins per liter of plasma, and from 20 to 100 mumol per liter of urine. The sensitivity may be improved two to five times by using precolumn loading, direct sample clean-up and automatic injection. The stability of the cephalosporins in plasma, urine and water and the reproducibility and accuracy of the methods are reported.

Topics: Cefotaxime; Cefotiam; Cefsulodin; Cefuroxime; Cephalexin; Cephalosporins; Cephradine; Chromatography, High Pressure Liquid; Humans; Microchemistry; Structure-Activity Relationship

The renal excretory mechanism of cefmenoxime in rabbits was compared with that of 6 other cephalosporins (cefotaxime, deacetylcefotaxime, cefotiam, cefazolin, cephaloridine, and cefsulodin). The clearance ratios (Cf-Drug/CInulin=CRf) of cefmenoxime (337) and cefazolin (73) were considerably higher than those of the 5 other cephalosporins (0.9-20). When p-amino-hippurate (PAH) was administered concurrently with each of the cephalosporins, the CRf values of the cephalosporins except for cefsulodin were significantly decreased. These findings indicate that cefmenoxime and the 5 other cephalosporins except cefsulodin are actively incorporated in the proximal tubular cells and secreted into the tubular lumen. In the case of cefotiam and cefsulodin, glomerular filtration tended to exceed urinary excretion with highest dose of PAH (40 mg/kg/minute), suggesting the possibility of tubular reabsorption of these drugs. On the other hand, glomerular filtration of cefmenoxime and the 4 other cephalosporins did not exceed urinary excretion. The drug concentration ratio of the cortex to medulla indicated that the tubular cell level of cefmenoxime was lower than, higher than, and similar to those of cephaloridine, cefotaxime, and the remaining cephalosporins, respectively. These results demonstrate that the renal excretory mechanisms of cefmenoxime is similar to that of cefazolin but not to that of the remaining cephalosporins.

Topics: Aminohippuric Acids; Animals; Binding, Competitive; Blood Proteins; Cefazolin; Cefmenoxime; Cefotaxime; Cefotiam; Cefsulodin; Cephaloridine; Cephalosporins; Inulin; Kidney; Male; p-Aminohippuric Acid; Protein Binding; Rabbits