DETECTION OF CALCIUM-BINDING PROTEINS IN VENOM AND DUVERNOYS GLANDS OF SOUTH-AMERICAN SNAKES AND THEIR SECRETIONS

Calcium-binding proteins (CaBPs) have been described as involved in th e stimulus-secretion coupling mechanisms in secretory glands. CaBPs we re revealed with Ca-45, after electrophoresis in SDS-PAGE and transfer ence to Zeta probe membranes, in Duvernoy's or venom gland homogenates from three families of South American snakes: Viperidae (Bothrops jar araca and Crotalus durissus terrificus); Elapidae (Micrurus corallinus ), and Colubridae (Phylodrias patagoniensis and Oxyrhopus trigeminus). A band with an estimated molecular weight of 12 KDa was found in all glands studied. Bands with 17, 28, and 67 KDa were found in all glands , except in O. trigeminus Duvernoy's,aland. A 18 KDa band was found in Viperidae and Elapidae venom glands, and a 88 KDa band was observed o nly in Viperidae venom,oland homogenates. Some of these CaBPs were ide ntified by Western blotting or by immunohistochemistry, as parvalbumin (12 KDa) and calbindin (28 KDa). When the secretion of these glands w ere analyzed, CaBPs were detected only in B. jararaca venom, with band s of 14, 35, 42, and 72 KDa. The profile of CaBPs was not modified at different phases of the secretory cycle of the glands, as well as afte r isoproterenol treatment. (C) 1997 Elsevier Science Inc.