Study of the influence of haemodialysis on the β-methyl-digoxin levels in uraemic patients
- 5 Downloads
This study was undertaken to establish the plasma pharmacokinetics of β-methyl-digoxin (βmd) in 8 normal subjects (group 1) and 17 uraemic patients (group 2, not undergoing dialysis; group 3, undergoing dialysis). Blood samples were collected serially up to 5 hrs after an initial stimulus of 0.2 mg βmd i.v. βmd was determined both in serum and in dialysate by digoxin radioimmunoassay after having verified the following parameters: the immunological similarity between digoxin and βmd; the possibility of evaluating βmd in dialysate; the quantitative recovery of βmd both in serum and in dialysate. At 15 min after stimulus, the following βmd peaks occurred: 5.82, 3.70 and 6.00 ng/ml for groups 1, 2 and 3, respectively, with a significant difference (p<0.02) between groups 1 and 2 and between groups 2 and 3 (p<0.02) up to 1 h after stimulus. For each group the rapid, mean and slow βmd half-times (T 1/2) were calculated. The three T 1/2 values differing from each other but being related to the different initial βmd concentrations, the angular coefficients of the disappearance regression lines (taken as parameters related to the βmd disappearance rates, dr) were plotted against the βmd concentrations expressed as % of their highest value corresponding to the respective rapid T 1/2. From this approach, it can be deduced that the dr of group 1 is much higher than the dr of groups 2 and 3, which are similar. This finding, together with the consideration that we never found βmd in dialysate, permits the conclusion that the distribution rate of βmd to the tissues is significatively higher in normal than in uraemic patients and that it does not change during dialysis treatment.
Key-wordsDialysate Digoxin radioimmunoassay Serum disappearance rate Uraemia
Unable to display preview. Download preview PDF.
- 1).Carbonin P., Bellocci F., Greco A. V., Cocchi A., Zecchi P.: Importanza e limiti del dosaggio radioimmunologico della digitalemia, determinata in diverse situazioni morbose (scompenso di circolo, cirrosi epatica, disprotidemia mielomatosa, gastroenteropatia) dopo somministrazione di β-metildigossina — In: Atti del Convegno di studio sulla digitale. Bergamo, 24–25 novembre 1973; p. 171.Google Scholar
- 5).Rennekamp H., Rennekamp C., Bergmann K. V., Abshagen U., Rietbrock N.: Metabolism and Pharmacokinetics of 4’”-Methyldigoxin in Man — Naunyn-Schmiedeberg’s Arch. exp. Path. Pharmak.274 (Suppl.), 91, 1972.Google Scholar
- 6).Strobach H., Greeff K., Horster F. A., Wildmeister W.: Radioimmunoassays for the Determination of the Serum Digoxin Level after Application of Digoxin and Digoxin Derivates in Man — Naunyn-Schmiedeberg’s Arch. exp. Path. Pharmak.274 (Suppl.), 113, 1972.Google Scholar
- 7).Tecniche standard per la misura del volume dei globuli rossi e del plasma — Relazione dell’ICSH (Comitato internazionale per la standardizzazione ematica), 1973.Google Scholar
- 8).Tronconi L., Recusani F., Bramucci E., De Servi S., Zanetta R., Scalambro A.: Valutazione degli effetti della β-metildigossina in soggetti sani e cardiopatici mediante metodiche incruente (poligramma, apicogramma) con contemporanea determinazione della digossinemia — In: Atti del Convegno di studio sulla digitale. Bergamo, 24–25 novembre 1973; p. 153.Google Scholar