Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0085580 (essential hypertension)
 14,686 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The contact phase of blood coagulation in a group of patients suffering from essential hypertension was studied before and after captopril administration. The baseline levels of factor XII, factor XI and plasminogen were significantly higher than in normals and correlated with baseline diastolic blood pressure levels. On the contrary, plasma prekallikrein was not significantly different from normal. These results suggest the presence of a hypercoagulable state in essential hypertension. After captopril administration, factor XII, factor XI and prekallikrein rapidly decreased, perhaps as a consequence of the drug's effect on the vascular endothelial surface. There was no correlation between the changes of active and inactive renin and the changes of prekallikrein and plasminogen levels. Our data do not support the view that factor XII-plasma kallikrein or plasmin dependent pathways are involved in the activation of inactive renin in vivo. Captopril, by provoking rapid pressure changes, appears to be able to affect the clotting system.
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PMID:The contact phase of blood coagulation and renin activation in essential hypertension before and after captopril. 638 34

Essential hypertension is often accompanied by abnormalities of the coagulation/fibrinolytic system, predisposing to a procoagulant state. The aim of the present study was to compare the effects of atenolol (beta1-blocker agent) and irbesartan (angiotensin II type 1 receptor antagonist) on plasma levels of hemostatic/fibrinolytic and endothelial function markers in a cohort of previously untreated hypertensives. Fifty-four patients were randomly assigned to atenolol 25 to 150 mg (26 patients) or irbesartan 75 to 300 mg (28 patients). The plasma levels of plasminogen activator inhibitor-1 antigen, thrombomodulin, tissue factor pathway inhibitor antigen, fibrinogen, and factor XII were determined before and after 6 months of therapy. Age, gender distribution, body mass index, lipid profile, and baseline values of the measured markers were similar in both groups. Baseline values for systolic and diastolic blood pressure, as well as the reduction after treatment, were not significantly different between the two groups. Treatment with irbesartan was associated with a significant decrease in the levels of all the parameters. Similar findings were observed in the atenolol group, except for factor XII and tissue factor pathway inhibitor levels, which were not significantly decreased in this group. The reduction, however, of fibrinogen, plasminogen activator inhibitor-1, and thrombomodulin was significantly greater in the irbesartan than in the atenolol group. In conclusion, the results indicated that, despite an equally controlled blood pressure, 6-month therapy with irbesartan was associated with a more favorable modification of hemostatic/fibrinolytic status than atenolol.
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PMID:Fibrinolytic/hemostatic variables in arterial hypertension: response to treatment with irbesartan or atenolol. 1093 70

It has been previously shown that essential hypertension (EH) is associated with coagulation-fibrinolytic balance disorders. Our study was conducted in order to investigate disturbances in coagulation-fibrinolysis in offsprings of hypertensive parents. Two groups were studied: 44 healthy normotensive individuals (17 male, 27 female, age range 12-22 years) with a documented family history of hypertension and 33 individuals (14 male, 19 female, age range 11-21 years) without a family history of essential hypertension. The following parameters were determined in both groups: plasminogen activator inhibitor-1 antigen, tissue plasminogen activator antigen, fibrinogen, fibrin degradation products, thrombomodulin, protein S antigen, protein C activity, von Willebrand factor Ag, factor VII and factor XII activity. Additionally, systolic and diastolic blood pressure, insulin levels, blood lipids and heart rate were determined. The two groups were not found to have differences with respect to age, gender, body mass index, blood lipids and insulin levels. Hypertensive offsprings had significantly higher plasma levels of plasminogen activator inhibitor-1 antigen, fibrinogen, fibrin degradation products, protein S antigen and factor XII activity, while no differences were observed to the other haemostatic variables studied. Hence, offsprings of hypertensives had significantly higher diastolic blood pressure and heart rate. In conclusion, alterations regarding blood pressure, heart rate and fibrinolytic function exist in offsprings of hypertensive parents compared to individuals without family history of hypertension.
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PMID:Parental history of hypertension is associated with coagulation-fibrinolytic balance disorders. 1464 78

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

Prekallikrein (PK) is one of the clotting factors involved in the contact phase of blood. PK has an important historical role as its deficiency state represents the second instance of a clotting defect without bleeding manifestations, the first one being factor XII deficiency. PK deficiency is a rare clotting disorder. Moreover, only 11 patients have been investigated so far by molecular biology techniques. In this article, we briefly review some of the history around PK and also present some recent data on a newly identified family from Argentina suffering from PK deficiency. Two patients are homozygous whereas other family members are heterozygous. PK activity and antigen are 1% of normal in the homozygotes and around 60 to 70% of normal in the heterozygotes. As expected, all patients are asymptomatic of bleeding or thrombosis presentations. However, the two homozygotes showed essential hypertension. The PK deficiency in this family is due to a new mutation (Arg541Gln) in exon 14. The defect segregates together with a known polymorphism, Asn124Ser, in exon 5. The significance of the presence of hypertension in the two homozygotes is discussed in view of the extra coagulation effects of PK on vasodilation, vessel permeability, and the control of blood pressure. Structure function analysis indicates that the substitution of Arg with Gln probably impedes the transmembrane diffusion of the molecule, which therefore cannot be secreted in the homozygotes. The presence of hypertension in patients with PK deficiency has been previously reported in some but not all patients. Future research activities will probably concentrate on the effect of PK and other contact phase factors on the vascular system.
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PMID:The old and the new in prekallikrein deficiency: historical context and a family from Argentina with PK deficiency due to a new mutation (Arg541Gln) in exon 14 associated with a common polymorphysm (Asn124Ser) in exon 5. 2507 49