Summary
Intravenous injection of E. coli endotoxin (ETX), of adrenaline (AD) or of carbamylcholine
(CBCH), caused fibrinolytic activity (FA), directly detectable on plasminogen-rich
fibrin plates, to appear in the plasma of the rat. Adrenodemedul- lation abolished
responses to ETX or CBCH, but enhanced those to AD. Rats given ETX exhibited marked
hypotension, followed by a compensatory phase of normotension abolished by adrenodemedullation
and significantly attenuated by phenoxy- benzamine, an a-adrenergic blocking agent
which however failed to block FA caused by either ETX or AD. Aspirin, but not indomethacin,
inhibited FA evoked by ETX, AD or CBCH. These results suggest that FA evoked by ETX
in the rat is caused by AD released from the adrenal gland and does involve the fatty
acid cyclooxygenase system.
Keywords
Fibrinolysis - Endotoxin - Adrenaline - Aspirin