Molecular diversity of snake venom nerve growth factors.

Nerve growth factor (NGF) is a protein which stimulates the differentiation and maintenance of sympathetic and embryonic sensory neurons. Snake venoms are a rich source of NGF. Due to small quantities it is sometimes difficult and laborious to isolate NGF from the venoms. In this study the use of Ni-NTA-agarose for isolation of NGF is studied. Anti-Vipera lebetina NGF antibodies were used for identification of NGF during Ni-NTA-agarose fractionation as well as for cross-reaction studies with 21 snake venoms. All studied venoms contained NGF. The molecular masses of the NGFs from Echis ocellatus, Agkistrodon contortrix contortrix, A. bilineatus, A. blomhoffii, A. saxatilis, Calloselasma rhodostoma, Bothrops jararaca and B. lanceolatus were determined for the first time. Some previous results of the NGF studies are revaluated.