MICE SKELETAL MUSCLE REGENERATION AFTER BEING DAMAGED BY Bothrops jararacussu VENOM: EFFECT OF HEPARIN

CALIL-ELIAS, S.; OLIVEIRA, J.S.; TOMAZ, M.A.; FERNANDES, F.F.A; MARTINEZ, A.M.B; MELO, P.A.

Departamento de Farmacologia Básica e Clínica and Departamento de Histologia e Embriologia, ICB, UFRJ. 21941-560, Rio de Janeiro, RJ, Brasil.

We have previously shown that heparin antagonizes the myotoxic effect of Bothrops jararacussu venom on mice EDL (Extensor digitorum longus) muscle (Calil-Elias, et. al., 2002). We analyzed the effect of treatment, by the intravenous route, with either heparin (H – 10 mg/Kg), low molecular weight heparin (LMWH – 10 mg/Kg), or specific antivenom (AV – 1 mL/Kg) between 15 and 240 min. after the venom injection. Assessment was performed by electronic microscopy and the measurement of creatinekinase (CK) content. 21 days after the injection of the venom, the animals were killed under anesthesia with ether, and the EDL muscles were removed by dissection. A group of isolated muscles was homogenized for measurement of total CK content while another group was immersed in fixative solution and processed for electronic microscopy. The venom induced a 38% decrease in CK content compared to normal, and after treatment with H and LMWH the decrease was 30.5% and 1.3%, respectively. Our observations in electronic microscopy showed that the treatment with H and LMWH caused a complete regeneration of myofibers and other elements of intracellular organization. On the other hand, the animals that received only the venom injection showed regenerated cells that were completely disorganized. These data indicated that heparin improves the regeneration of EDL muscle damaged by B. jararacussu venom.

Supported by: CAPES, FAPERJ, CNPq-PRONEX, FUJB-UFRJ.

CORRESPONDENCE TO:

CALIL-ELIAS, S., Departamento de Farmacologia Básica e Clínica, ICB, UFRJ, 21941-560, Rio de Janeiro, RJ, Brasil, Email: sabrinac@antares.com.br