The present work concerns our studies to search for factor(s) which may influence
the hemostatic process in or around metastasis of tumours. We studied the platelet
aggregating property of a methyl cholanthrene induced experimental tumour. Platelet
aggregating material was found to be different from the known aggregating agents like
thrombin, ADP, collagen, thromboxane A2 and trypsin. It depends on a critical level of calcium for its action. PAM is a high
molecular weight substance which contains sialic acid. It is trypsin and plasmin insensitive.
The activity of this substance is not being destroyed by phospholipase-C. Metabolic
study indicates that PAM acts by mitochondrial energy metabolic pathway of the platelets.
Keywords
Platelet aggregating material (PAM) - Tumour extract - Inhibitors of PAM