Biochemical nature and biological activity of the vascular permeability factor of bovine platelets

✍ Scribed by Yoshihiro Ashihara

• Publisher: John Wiley and Sons
• Year: 1988
• Tongue: English
• Weight: 868 KB
• Volume: 2
• Category: Article
• ISSN: 0887-8013
• DOI: 10.1002/jcla.1860020202

✦ Synopsis

Bovine vascular permeability factor (BVPF) was purified from the a-granule acid extract of platelets (BPAE) by ion-exchange and gel-filtration chromatography. BVPF is a cationic protein with an isoelectric point of 8.8. As determined by gel filtration using a Superose 12 column, there appear to be three kinds of BVPF with molecular weights of 30,000, 300,000, and >450,000. After heat treatment of BPAE, however, BVPF was eluted in a fraction with a molecular weight of 30,000. Vascular permeability increased as much as 2.3fold with heat treatment of BPAE at 56OC for 30 minutes and was retained even after heat treatment at 8OOC. BVPF was also stable to acid or alkaline treatment, but it was sensitive to proteases or thiol reagents, especially pepsin and 2-mercaptoethanol. After injection of BVPF into the dorsal skin of rabbits, enhancement of vascular Permeability was reconfirmed by 3 minutes of observation electron microscopically. One hour later, exudation had increased at the injection sites, and there was associated inflammatory cell infiltration with occasional strands of fibrin.