Humoral regulation of thrombopoiesis in man

Plasma was obtained before and after plateletpheresis-induced thrombocytopenia from two healthy male subjects during periods of ethanol ingestion and abstinence. Autologous reinfusion of these plasmas was performed at a later date when both subjects were hematologically normal. Eight thrombopoietically active plasmas produced an increased percent of immature megakaryocytes 24 hr after reinfusion and a peak rise in platelet count (averaging 148% of baseline values) at 5.8 days. Similar changes were not found with inactive plasmas, plasma collected at the end of a "sham" plateletpheresis, or plasma collected after 8 hr of ingestion of 296 gm of ethanol. A transient increase in TSA was found in plasmas collected at the end of plateletpheresis during abstinence, but this activity was not detected 12 hr later. The rapid disappearance of TSA, despite persistent thrombocytopenia, coincided with the appearance of an increased percent of immature magakaryocytes in the bone marrow. Elevated TSA was also noted at the end of plateletpheresis during ethanol ingestion but, in contrast to events during abstinence, remained elevated as long as ethanol ingestion continued.