Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0848237 (acute stress)
 4,619 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Twenty-seven young adults (mean age 46) with ischemic cerebrovascular disease (ICD) were reinvestigated about 5 years after discharge and compared to 67 healthy controls. Factor VIII related antigen was again found significantly (p less than 0.005 and p less than 0.001) increased in male as well as female patients and a significant (r = 0.66, p less than 0.001) correlation was found with earlier data. Factor VIII biological activity was again found increased, significantly (p less than 0.001) in males. In contrast to earlier results antithrombin antigen and activity were significantly (p less than 0.001) decreased in males. This finding and decreased levels of factor XII in female patients (p less than 0.001) and of prekallikrein in male patients (p less than 0.01) could reflect disturbed regulatory functions or possibly constitutional differences. As in most subjects no increase of fibrinopeptide A was found, there was no sign of continuous activation of the whole coagulation sequence. Since hemostatic abnormalities were unrelated to acute phase reacting proteins they were obviously of a different nature than unspecific response to tissue damage and acute stress. High levels of factor VIII and low levels of antithrombin imply that the coagulation system could be more easily activated when other factors coincide, e.g. intimal lesions in carotide arteries.
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PMID:A study of hemostasis in ischemic cerebrovascular disease: IV. A five year follow-up of some blood coagulation parameters also including fibrinopeptide A, factor XII and prekallikrein. 681 2

A new hypothesis is presented on the function of factor XII, which is postulated to be a "missing link" between acute stress and transient hypercoagulability. The implications of this idea are developed to show how chronic stress, which involves activation of hypertension and migraine as well as hypercoagulability, can cause of cerebrovascular disease. "Acute stress" is defined as "the normal short-term physiological response to the perception of major threats or demands". "Chronic stress" is "the abnormal ongoing physiological response to the continuing perception of unresolvable major threats or demands". The factor XII hypothesis is as follows: Acute stress includes release of epinephrine by the adrenal medulla. Epinephrine activates platelets by binding to alpha-2A adrenergic receptors. Activated platelets convert pre-bound factor XII to its active form, which then initiates the intrinsic coagulation cascade. This can be called the "activated platelet initiation pathway" for coagulation. Neither tissue factor nor pre-formed thrombin is required. Thrombosis proceeds to completion, but only a minute amount of thrombin is formed, and the process normally stops at this point. In people who lapse into a state of chronic stress, essential hypertension, which is also a manifestation of stress, synergizes with hypercoagulability: there is both a baseline rise in blood pressure and systemic platelet activation as well as superimposed labile rises of both. Upregulation of these two stress parameters is atherogenic: epinephrine-activated platelets stimulating thrombin formation interact with endothelial cells activated by angiotensin II to cause, first, smooth muscle cell proliferation, which is a histological hallmark of atherosclerosis, and, lastly, a symptomatic thrombotic occlusion-the stroke. The migraine symptoms which often accompany this process are a marker of chronic stress and ongoing pathophysiologic damage. Therapeutic predictions are made regarding novel ways of blocking stress-induced hypercoagulability and hypertension. Hypercoagulability could be targeted by monoclonal antibodies directed against the platelet-specific alpha-2 adrenergic receptor or the (putative) platelet receptor for Factor XII; hypertension could be treated with monoclonal antibodies directed against the beta-adrenergic receptor in the juxtaglomerular apparatus or by surgical denervation of the kidneys, either of which would decrease the renin release which helps drive the hypertension.
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PMID:Factor XII (Hageman factor) is a missing link between stress and hypercoagulability and plays an important role in the pathophysiology of ischemic stroke. 1675 26