Plasma concentration-dependent suppression of endogenous hydrocortisone in the horse after intramuscular administration of dexamethasone-21-isonicotinate

2014 ◽  
Vol 38 (3) ◽  
pp. 235-242 ◽  
Author(s):  
C. Ekstrand ◽  
U. Bondesson ◽  
J. Gabrielsson ◽  
M. Hedeland ◽  
P. Kallings ◽  
...  
2000 ◽  
Vol 92 (2) ◽  
pp. 376-376 ◽  
Author(s):  
Lynne M. Reynolds ◽  
Andrew Infosino ◽  
Ronald Brown ◽  
Jim Hsu ◽  
Dennis M. Fisher

Background A nondepolarizing muscle relaxant with an onset and offset profile similar to succinylcholine is desirable for pediatric anesthesia. The onset and offset of rapacuronium are rapid in children. In the current study, the authors determined its pharmacokinetic characteristics in children. In addition to administering rapacuronium by the usual intravenous route, the authors also gave rapacuronium intramuscularly to determine uptake characteristics and bioavailability. Methods Forty unpremedicated patients aged 2 months to 3 yr were anesthetized with halothane, 0.82-1.0% end-tidal concentration. When anesthetic conditions were stable, rapacuronium was injected either into a peripheral vein (2 mg/kg for infants, 3 mg/kg for children) or a deltoid muscle (2.8 mg/kg for infants, 4.8 mg/kg for children). Four venous plasma samples were obtained from each subject 2-240 min after rapacuronium administration. A mixed-effects population pharmacokinetic analysis was applied to these values to determine bioavailability, absorption rate constant, and time to peak plasma concentration with intramuscular administration. Results Plasma clearance was 4.77 ml x kg(-1) x min(-1) + 8.48 ml/min. Intramuscular bioavailability averaged 56%. Absorption from the intramuscular depot had two rate constants: 0.0491 min(-1) (72.4% of absorbed drug) and 0.0110 min(-1) (27.6% of the absorbed drug). Simulation indicated that plasma concentration peaks 4.0 and 5.0 min after intramuscular rapacuronium in infants and children, respectively, and that, at 30 min, less than 25% of the administered dose remains to be absorbed from the intramuscular depot. Conclusions In infants and children, rapacuronium's clearance and steady state distribution volume are less than in adults. After intramuscular administration, bioavailability is 56%, and plasma rapacuronium concentrations peak within 4 or 5 min.


1981 ◽  
Vol 377 (1 Myasthenia Gr) ◽  
pp. 816-817 ◽  
Author(s):  
T. N. Calvey ◽  
N. E. Williams ◽  
K. Chan ◽  
A. Dehghan ◽  
S. M. Somani

1996 ◽  
Vol 75 (02) ◽  
pp. 270-274 ◽  
Author(s):  
Benget Zöller ◽  
Johan Holm ◽  
Peter Svensson ◽  
Björn Dahlbäck

SummaryInherited resistance to activated protein C (APC-resistance), caused by a point mutation in the factor V gene leading to replacement of Arg(R)506 with a Gin (Q), and inherited protein S deficiency are associated with functional impairment of the protein C anticoagulant system, yielding lifelong hypercoagulability and increased risk of thrombosis. APC-resistance is often an additional genetic risk factor in thrombosis-prone protein S deficient families. The plasma concentration of prothrombin fragment 1+2 (F1+2), which is a marker of hyper-coagulable states, was measured in 205 members of 34 thrombosis-prone families harbouring the Arg506 to Gin mutation (APC-resistance) and/or inherited protein S deficiency. The plasma concentration of F1+2 was significantly higher both in 38 individuals carrying the FV:Q506 mutation in heterozygous state (1.7 ± 0.7 nM; mean ± SD) and in 48 protein S deficient cases (1.9 ± 0.9 nM), than in 100 unaffected relatives (1.3 ±0.5 nM). Warfarin therapy decreased the F1+2 levels, even in those four patients who had combined defects (0.5 ± 0.3 nM). Our results agree with the hypothesis that individuals with APC-resistance or protein S deficiency have an imbalance between pro- and anti-coagulant forces leading to increased thrombin generation and a hypercoagulable state.


1969 ◽  
Vol 21 (02) ◽  
pp. 320-324 ◽  
Author(s):  
K Seiler ◽  
F Duckert

SummaryA case of severe Marcoumar intoxication is described. Eleven hours after the intake a plasma concentration of 15.75 µg/ml was found which corresponds approximately to the 5-fold therapeutic concentration. Repeated administration of vitamin K1 made it possible to avoid extreme lowering of the activity of the clotting factors II, VII and X and to prevent bleeding. Side effects were not observed. The biologic half-life of Phenprocoumon has been found to be shortened at high plasma concentration (3.7 instead of 5.9 days). It is probable that in extreme concentration the drug is less strongly bound to the plasma proteins.


1997 ◽  
Vol 77 (02) ◽  
pp. 248-251 ◽  
Author(s):  
Lena Norlund ◽  
Johan Holm ◽  
Bengt Zöller ◽  
Ann-Kristin Öhlin

SummaryEndothelial dysfunction and haemostatic imbalance are believed to be important aetiological factors in the development of acute coronary syndromes. Thrombomodulin (TM) is an integral membrane protein crucial for normal endothelial function and activation of the protein C anticoagulant pathway. We have investigated the importance of a common C/T dimorphism in the TM gene (nucleotide 1418) for development of premature myocardial infarction (MI). The C/T dimorphism predicts an Ala455 to Val replacement in the sixth EGF-like domain of TM. The dimorphism was investigated in 97 MI survivors and 159 healthy controls. The C allele was significantly more frequent among patients than controls (p = 0.035). The allele frequency for the C allele was 0.82 in the patients and 0.72 in the control group. The plasma concentration of TM was investigated among healthy controls but was not related to the C/T dimorphism. In conclusion, the association of the C allele with premature MI, suggests that the TM gene and the C/T dimorphism may be aetiological factors involved in the pathogenesis of MI. Possibly, the Ala455 to Val replacement may affect the function of the TM molecule and the activation of the protein C anticoagulant pathway.


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