Electronic Resource
Springer
Naunyn-Schmiedeberg's archives of pharmacology
272 (1972), S. 32-45
ISSN:
1432-1912
Keywords:
Cardioglycoside
;
Labelled Compound
;
Absorption
;
Cardiac Output
;
Guinea-Pig
Source:
Springer Online Journal Archives 1860-2000
Topics:
Medicine
Notes:
Summary Glycosides were injected into a ligated loop of the small intestine of guinea-pigs under urethane anaesthesia. From the residual radioactivity in the intestinal loop at various times after the injection the amount absorbed was determined and from that the rate of absorption, assuming exponential absorption. β-Methyl-digoxin was absorbed more rapidly than digoxin and its derivatives β-acetyl-digoxin and lanatoside C but slower than digitoxin. β-Methyl-digoxin was much better absorbed from a suspension than from a solution; this caused the difference from digitoxin to disappear to a large extent. The high rate of absorption of β-methyl-digoxin in humans is probably explicable in this way. The rate of absorption of β-methyl-digoxin was independent of the dose until the appearance of arrhythmias; it decreased with progressing intoxication. Absorption was delayed when cardiac output was decreased by barbital anaesthesia. The amount absorbed at the onset of arrhythmias can be calculated from the injected dose, the rate of absorption and the time. For β-methyl-digoxin and digoxin it corresponded to the effective doses determined by intravenous infusion and to the cardiotoxicity after intraduodenal injection. The cardiotoxicity of β-acetyl-digoxin and digitoxin was less than that expected from the amounts absorbed suggesting metabolic inactivation during absorption. The relative enteral activity is not only determined by the absorption but also by the rate of elimination. The rate at which the material should leave the intestine in order to maintain arrhythmia was calculated. It was considerably greater for digitoxin than for β-methyl-digoxin or digoxin.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00498792
Permalink
| Library |
Location |
Call Number |
Volume/Issue/Year |
Availability |
