Stress is involved in the development of diseases related to abnormal
hemostasis. Thrombosis may develop whenever the dynamic balance between
prothrombotic and antithrombotic processes become altered Recently,
renirt aru3iotensin system is considered to be a stress hormone response
system. The aim of the present work was to clarify the effect of
acute and chronic stress on the prothrombotic and antithrombotic activity
and to study the role of angiotensin II in these stress-induced changes.
The results of this work showed that acute ether stress and chronic isolation
stress lead to suppression of both intrinsic and extrinsic coagulability
manifested by a decrease in the fibrinogen concentration and a decrease
in the activity of factors VII and X, at the same time acute and chronic
stress caused a decrease in the antithrombotic activity indicated by a reduction
in the activity of antithrotnbin III. This means that hemostatic balance
is probably maintained at a low level, this make it difficult to hypothesize
the existence of a hypercoagulable or a hypocoagulable state
during stress. These changes can not be attributed to hemodilution since
we found that stress causes hemoconcentration indicated by increased
packed cell volume. The results of this work showed, also, that, these
stress-induced hemostatic changes was prevented by pretreatment with
the angiotensirt converting enzyme inhibitor fperindopria this means that
these stress-induced hemostatic changes is mediated, at least partially,
through the renin angiotensin system. |
