Protective effect of pantethine on experimental thrombocytopenia in the rat.

The effects of pantethine on circulating platelet counts and platelet functions were studied in normal and experimentally produced thrombocytopenic rats. Administration of pantethine to normal animals did not cause any alterations in both platelet count and function except for a slight enhancement of intravascular platelet aggregation induced by collagen or neuramindase. Injection of anti-rat platelet rabbit serum into rats resulted in acute thrombocytopenia. Administration of pantethine prior to the antiserum promoted recovery from the thrombocytopenia in a dose dependent manner, but administration of the drug after development of the thrombocytopenia was not effective. A similar result was obtained with a transietnt thrombocytopenia induced by exchange transfusion with platelet poor blood. Regardless of whether animals were treated with pantethine or not, the platelets newly generated during the course of recovery from thrombocytopenia were essentially normal in the function tested in vitro. A more chronic thrombocytopenia induced by repeated injections of the antiserum was prevented, to some significant degree, by daily administration of pantethine throughout the experimental period. In contrast to these, such effect of pantethine was not observed with the thrombocytopenia models produced bynitrogen mustard N-oxide and neuraminidase. These findings were idscussed in relation to mechanism of the action of pantethine and to possible clinical application to the drug to thrombocytopenia.