Bleeding Vessels

In self-defence some snakes, such as vipers, will bite humans, releasing venom through their fangs. This can cause a variety of symptoms, such as breathing difficulties, blurred vision, tissue damage, paralysis, and bleeding. Snake venom contains many different compounds, and snake venom haemorrhagic metalloproteinases (SVMPs) are particularly notable due to their destructive haemorrhagic action on blood vessels. There are three kinds of SVMPs – PI, PII, and PIII – with different haemorrhagic potential. PI spreads throughout the victim’s tissue; but PII and III (stained blue) preferentially localise (white areas) in the collagen of capillaries (green), where they degrade it, damaging its structure, and ultimately cause a haemorrhage. Differences in localisation could be an important reason why PII and PIII SVMPs so readily cause bleeding. We now have a better picture of the mechanism behind vessel damage and haemorrhaging caused by SVMPs.

Written by Katie Panteli

Katie Panteli

Writer

Katie, a Warwick Biomed graduate, works for a science-publishing house in London with some of the world's most respected scientific minds. She's most interested in human biology, anything and everything that makes us tick.

• Image from work by Cristina Herrera and colleagues
• Universidad de Costa Rica
• Originally published under a Creative Commons Licence (BY 4.0)
• Research published in PLOS Neglected Tropical Diseases, April 2015