Muscle and skin necrotizing and edema-forming activities of the Duvernoy’s gland secretion of the xenodontine colubrid Philodryas patagoniensis from the north-east of Argentina

MARÍA ELISA PEICHOTO; OFELIA ACOSTA; LAURA LEIVA; PAMELA TEIBLER; SILVANA MARUÑAK; RAQUEL RUÍZ

TOXICON

Elsevier Science

Lugar: Oxford; Año: 2004 vol. 44 p. 589 - 596

0041-0101

Philodryas patagoniensis is a colubrid snake spread by all South America, but very little is known about composition and biological activities of Duvernoy’s gland secretion. In order to characterize it, in this work edematogenic, dermonecrotic and myonecrotic activities were studied. For edematogenic activity solutions containing different amounts of secretion were injected s.c. in the right foot pad of mice, both feet were cut off and weighed individually. For myonecrotic activity mice were injected i.m. with solutions containing 40 ìg of secretion, at various time intervals mice were bled to determinate serum creatine kinase activity and gastrocnemius muscles were extracted to microscopic examination (Hematoxylin-Eosin stain). For dermonecrotic activity solutions containing different amounts of secretion were injected into the shaved dorsal skin of mice, the necrotic lesion was measured on the inner surface of the skin and trimmed to microscopic examination (Hematoxylin-Eosin stain). Phospholipase A2 activity was evaluated using a kinetic method. Results showed that Philodryas patagoniensis Duvernoy’s gland secretion exhibits a high edematogenic activity and moderate myonecrotic and dermonecrotic activities, lacking phospholipase A2 effect. Regarding to edema, a 30 % increase in the weight was produced by injecting 0.26 ìg of DG secretion. Microscopically, myonecrosis reached its highest intensity 12 hr after injection, which was also demonstrated by serum creatine kinase levels. Dermonecrosis was proportional to the amount of DG secretion injected, obtaining a minimum necrotizing dose of 15.72 ìg. Myonecrotic, edematogenic and dermonecrotic activities were inhibited when the secretion was pre-incubated with 1 mM Na2EDTA. This suggests us that the enzymes responsible for those activities are mostly metalloprotienases. All the studies carried out up to now demonstrate the potential toxicity of Philodryas patagoniensis Duvernoy’s gland secretion (which inhabits the north-east region of Argentina) and that the local lesions caused by this colubrid snake are very similar to those found in bothropic accidents. This latter suggests a more careful evaluation on the victims considering the medical treatment to be adopted.