Pharmacokinetics of Tityus serrulatus scorpion venom determined by enzyme-linked immunosorbent assay in the rat

Autor: A.C.T. Freire, A.P.L. Ferreira, C.R. Diniz, C. Cháves-Olórtegui, L. Freire-Maia, G.C. Santana
Rok vydání: 1996
Předmět:
Zdroj: Toxicon : official journal of the International Society on Toxinology. 34(9)
ISSN: 0041-0101
Popis: Experiments were performed in two groups of anaesthetized rats to study the genesis of pulmonary oedema and to determine the pharmacokinetic parameters following a subcutaneous (s.c.) injection of Tityus serrulatus scorpion venom. In group 1, the rats were anaesthetized with pentobarbital (4 mg/100 g, i.p.); the s.c. injection of scorpion venom at the dose of 50 ug/100 g did not induce arterial hypertension, but unilateral pulmonary oedema was observed in three of six rats. The injection of a higher dose of venom (200 μg/100 g, N = 6) induced arterial hypertension and bilateral (N = 3) or unilateral (N = 1) pulmonary oedema. These data indicate that it is possible to evoke unilateral pulmonary oedema without previous arterial hypertension induced by the venom. For the study of pharmacokinetic parameters a second group of six rats was anaesthetized with urethane (140 mg/ 100 g, i.p.) and the venom injected at a dose of 200 ug/100 g, s.c. The plasma concentrations of venom were determined by enzyme-linked immunosorbent assay, at times 0, 5, 30, 60, 180, 360, and 720 min after venom injection. A biphasic curve was obtained with an ascending phase followed by a descending phase. The maximum plasma scorpion venom concentration was reached at 60 min. The pharmacokinetic parameters showed a fast absorption rate ( K a a = 0.058 min −1 ), a fast and high distribution of venom to tissues ( t 1 2 α = 31.50 min and Vdarea = 6800.47 ml.kg−1, respectively), a great affinity of the venom for the tissues (kct = 0.056 min−1 and KTC = 0.002 min−1) and a slow elimination half-life ( t 1 2 β = 173.25 min ).
Databáze: OpenAIRE
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