Cerastocytin - Inhibition

Inhibition

The effects of various inhibitors are not always consistent for thrombin and cerastocytin. Just as with thrombin, cerastocytin-activated platelet aggregation is inhibited by chlorpromazine, theophylline and mepacrine. However, neither hirudin, nor antithrombin III have any effect on cerastocytin-mediated clot formation even though both have been observed to inhibit thrombin-facilitated platelet clot formation. This data suggests that cerastocytin has distinct sites for platelet and fibrinopeptide binding because the two functions could be inhibited independently of each other. Additionally, some antibodies (such as LJIblO) that have been observed to inhibit thrombin, interfered with cerastocytin activity, but not with cerastotin. This data reinforces the concept that there a multiple toxins that are capable of producing similar physiological results via very different activation mechanisms.