Evidence of presynaptic and postsynaptic action of local anesthetics in rats
Braga, Angélica de Fátima de Assunção; Carvalho, Vanessa Henriques; Braga, Franklin Sarmento da Silva; Potério, Gloria Maria Braga; Santos, Filipe Nadir Caparica.
Acta cir. bras.;
28(11): 774-777, Nov. 2013.
Artigo
em Inglês
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| ID: vti-9106
Resumo
PURPOSE: To assess the probable actions of ropivacaine, 50% enantiomeric excess bupivacaine mixture (S75-R25) and levobupivacaine on neuromuscular transmission in vitro. METHODS: Thirty rats were distributed into groups (n=5) according to the drug used: ropivacaine, bupivacaine (S75-R25) and levobupivacaine. The concentration used for the three local anesthetics (LA) was 5 µg.mL.-1The following parameters were evaluated: 1) LA effects on membrane potential (MP) and miniature end plate potential (MEPP). A chick biventer cervicis preparation was also used to evaluate LA effects on the contracture response to acetylcholine. RESULTS: LA did not alter MP values and decreased the frequency and amplitude of MEPP. In a chick biventer cervicis preparation, bupivacaine (S75-R25) and levobupivacaine decreased the contracture response to acetylcholine with statistical significance, in comparison to ropivacaine. CONCLUSIONS: In the concentrations used, levobupivacaine and bupivacaine (S75-R25) exhibited presynaptic and postsynaptic actions evidenced by alterations in miniature end plate potentials and contracture response to acetylcholine. Ropivacaine only had a presynaptic action.(AU)
Biblioteca responsável:
BR1.1
Localização: BR68.1
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