Kinetic analysis of demethylation of 13C-aminopyrine in healthy dogs

Abstract

PCD appears to be the preferable variable for evaluation of hepatic demethylating capacity. Intravenous administration of 13C-aminopyrine leads to a consistent increase in PCD. Mean PCD peaked 45 minutes after administration, suggesting that blood sample collection 45 minutes after 13C-aminopyrine administration may be appropriate for use in estimating hepatic demethylating capacity.

Optimization of sample handling and processing for the carbon 13-labeled aminopyrine demethylation blood test and determination of a reference range for test results in healthy dogs

“…Consistent with findings of previous studies, [17][18][19][20] no clinically obvious adverse effects developed in any of the dogs during the study and the following 7 days. Despite the apparent safety of the 13 C-ADBT in the 75 dogs used in all studies [17][18][19][20] to date, no long-term hematologic or serum biochemical analyses have been performed as part of a more rigorous safety evaluation. Mild organ damage may be more important in dogs with compromised hepatic function.…”

“…This test involves IV administration of 13 C-aminopyrine and assessment of the PCD; it has been analytically validated and shown to be technically feasible. [17][18][19] In preliminary experiments in dogs, 20 the results of the 13 C-ADBT were similar to those obtained by use of the breath aminopyrine demethylation test in humans; there appeared to be an inverse correlation of PCD with increasing severity of hepatic disease (as determined histologically). However, the true usefulness of the 13 C-ADBT in dogs has yet to be defined.…”

Comparison of various doses of carbon 13-labeled aminopyrine for a carbon 13-labeled aminopyrine demethylation blood test in healthy dogs

“…Data for 13 C-aminopyrine administered at a dose of 2 mg/kg were collected during a kinetic study performed previously. 17 The remaining 3 doses of 13 C-aminopyrine were evaluated during various experimental periods so that doses were actually evaluated in the following order: 2, 5, 1, and 10 mg/kg. All dogs received the same dose during each experimental period to enhance the possibility of identifying potential adverse effects of repeated 13 C-aminopyrine administration.…”

“…In that study, 13 C-aminopyrine administered orally at a dose of 2 mg/kg to healthy dogs resulted in a detectible increase in the PCD in all dogs. Another study 17 was performed to evaluate the demethylation kinetics of 13 C-aminopyrine administered IV in healthy dogs and determine an appropriate parameter for quantification of aminopyrine demethylation. Results of that study indicated that IV administration of 13 C-aminopyrine, as previously detected for oral administration, does not result in any gross clinical adverse effects.…”

Liver Function Evaluation in Dogs by the Galactose Load Test

“…In this way quantitative indications about specific hepatic metabolic functions are obtained (Brockmoller and Root, 1994). Some of these tests were much used in the past and have subsequently been neglected, but a recent revaluation is progressing in human (Beker, 1998) and veterinary medicine (Moeller et al, 2004).…”