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Hemorrheological and humoral abnormalities and excessive platelet activity can predict the development of cardiovascular complications in patients with essential hypertension. A study was conducted to assess the influence of gender on these factors and the interrelations between changes in hemorrheology and the sympatho-adrenal system in 54 patients (18 women, 36 men) with essential hypertension (aged 39.6 +/- 9.7 years) and 25 healthy volunteers (10 women, 15 men; aged 36.0 +/- 7.2 years). A decrease in erythrocyte deformability (p < 0.01) was found in the hypertensive men compared with the hypertensive women. Hematocrit (p < 0.01), blood viscosity at the shear rates of 0.3 s-1 (p < 0.01) and 6 s-1 (p < 0.01), plasma viscosity (p < 0.01), erythrocyte aggregation (p < 0.01), and neuropeptide Y (p < 0.02) concentrations were higher in the hypertensive men than in the hypertensive women. A positive correlation between blood fibrinogen and serotonin was found in the pooled hypertensive group and in the hypertensive men (p < 0.01) and between blood viscosity (shear rate 6 s-1) and neuropeptide Y in the pooled hypertensive group (p < 0.01). Neuropeptide Y correlated with filtration time of 1 mL blood in the hypertensive men (p < 0.05) and in the pooled normotensive group (p < 0.01) and with beta-thromboglobulin in the hypertensive women (p < 0.001). A positive correlation was also found in the hypertensive men between erythrocyte and platelet aggregation (p < 0.01) and between beta-thromboglobulin and adrenaline (p < 0.01). Hemorrheological and humoral abnormalities are more pronounced in men than in women with essential hypertension and may contribute to the increased incidence of cardiovascular events in men.

Summary OBJECTIVE The purpose of this study was to evaluate the postural stimulation test before and after surgical treatment in patients with aldosterone-producing adenomas. DESIGN The retrospective study was made on patients with aldosterone producing adenomas. PATIENTS The postural stimulation test was analysed in 60 patients with surgically proven aldosterone producing adenoma and In 15 healthy volunteers. MEASUREMENTS The postural stimulation test was based on measurements of plasma aldosterone, cortisol and renin activity (PRA) at 0800 h and at noon after 4 hours ambulation. RESULTS The patients were divided into two groups according to the individual pattern of plasma aldosterone concentration following the postural test. Plasma aldosterone concentration decreased or did not change after 4 hours of standing in 42 patients (group 1,70% of total) and increased in 18 patients (group 2, 30% of total). Mean plasma aldosterone was significantly higher in group 1 than in group 2 (1325 ± 164 pmol/l (mean ± SE) and 538 ± 53 pmol/l, respectively). Mean plasma cortisol concentration after 4 hours of upright posture in both groups remained low (242 ± 35 vs 401 ± 63 nmol/l (group 1) and 317 ± 46 vs 367 ± 43 nmol/l (group 2). Mean PRA In both groups was suppressed after 4 hours of upright posture (0·2 ± 0·04 vs 0·2 ± 0·04 pmol/l/s and 0·3 ± 0·06 vs 0·1 ± 0·02 pmol/l/s, respectively). CONCLUSION Diverse changes In plasma aldosterone and cortisol found in response to the postural test may indicate pathogenetic heterogeneity amongst patients with aldosterone producing adenomas and should be considered during diagnosis of primary aldosteronlsm.

The interaction between catecholamines (CA) and ANP is not clearly established. The effects of excess endogenous CA on ANP secretion can be investigated in patients with pheochromocytoma. We studied 27 patients with surgically and histologically proven pheochromocytoma (P) aged 19-70 years. In 16 of these patients plasma ANP study was repeated after surgical removal of the tumour. The control group (C) consisted of 20 healthy volunteers aged 21-48 years. Moreover, 42 patients with uncomplicated mild to moderate essential hypertension (EH) aged 18-48 years were also studied. In P higher plasma ANP concentration versus C, EH was found (51.9 +/- 8.1; 25.5 +/- 1.5; 19.3 +/- 1.5 fmol/ml, respectively). In 16 patients with P, increased plasma ANP level (mean 63.3 +/- 12.6 fmol/ml) declined after surgical removal of the tumour (mean 22.4 +/- 2.9 fmol/ml). In the P patients no relationship was found between plasma ANP and hormonal patterns of the tumour or between plasma ANP and plasma catecholamines, whereas significant positive correlations between plasma ANP and both systolic and diastolic blood pressure and heart rate were demonstrated. These results suggest that excess CA produced by the chromaffin tumour induce ANP secretion via stimulation of adrenergic receptors. However, influence of the haemodynamic changes evoked by CA cannot be excluded. It is suggested that increased secretion of ANP may be of some importance in maintaining blood pressure homeostasis in patients with pheochromocytoma.

Neuropeptide-Y (NPY) is a peptide proposed to modulate the effect of the sympathetic nervous system on blood pressure control and contribute to the development of essential hypertension. To assess the possible influence of gender on its role, we evaluated plasma NPY, noradrenaline (NA) and adrenaline (A) concentrations in men and women with essential hypertension. No difference in NPY concentration was found between genders, but NPY concentration was elevated in both hypertensive men and women. NA levels were similar in all investigated hyper- and normotensives, while A was increased only in hypertensive men. These results suggest various patterns of sympatho-adrenal activity in gender subgroups of patients with essential hypertension.

In 64 kidney transplant patients (KTP) (35) treated by cyclosporine A (CyA)+ prednisone and 29 treated by azathioprine (Aza)+ prednisone and promethazine and in 15 healthy subjects plasma adrenalin (A), noradrenaline (NA), plasma renin activity (PRA) and mean arterial pressure (MAP) in basal conditions and after water immersion test (WI) were measured. In basal conditions the A and PRA were higher, but NA was normal. After WI statistically significant decrease of MAP, PRA, A and NA were observed in all examined groups. In KTP mean decrease MAP, PRA and A was higher, but NA lower than in normals. No significant correlation between A or NA and PRA, and MAP and A or NA was observed. In KTP the change in sympathetic+ activity was observed. Participation of catecholamines and renin in the pathogenesis of hypertension in KTP is not dominant. Kind of immunosuppressive therapy (CyA or Aza) haven't significant influence on A, NA nad PRA levels.

Platelet and plasma catecholamine concentrations were determined in 17 patients with surgically proven pheochromocytoma (mean age 42.3 years); in 31 patients with borderline hypertension (mean age 35.3 years) and in 9 healthy controls (mean age 39.3 years). Both platelet norepinephrine and epinephrine were significantly increased in patients with pheochromocytoma when compared with hypertensive and control groups (P less than .001). No correlation between platelet and plasma catecholamines was detected in all studied groups. The diagnostic accuracy of platelet catecholamine in pheochromocytoma is limited since increased platelet norepinephrine was found in 35.5% and increased platelet epinephrine was found in 19.4% of patients with essential hypertension.

In 106 patients with essential hypertension and different plasma renin activity several hormonal and metabolic factors were studied: urinary excretion of catecholamines, blood levels of cholesterol and triglycerides, levels of glycaemia and insulinaemia after glucose load and plasma fibrinolytic activity. The plasma renin activity in 46.2 percent of patients was normal, whereas in 25.5 percent it was low, and in 28.3 percent it was high. In patients with high plasma renin activity the excretion of noradrenaline and adrenaline was relatively high while that of dopamine was low. Significantly lower triglyceride levels were found in patients with low plasma renin activity in comparison with those with high and normal plasma renin activity. There was also a statistically significant difference in the euglobulin lysis time which was shorter in patients with low and longest in patients with normal plasma renin activity. The results of the study show that patients with different plasma renin activity may also differ in some hormonal and metabolic values.

Serial estimations of urinary excretion of free norepinephrine and epinephrine were made in 19 patients with recent myocardial infarction of varying clinical courses. An increase in urinary excretion of catecholamines during the acute phase was noted, more distinct in cases characterized by severe clinical course. In patients with myocardial infarction complicated by shock, circulatory insufficiency, and transient fall in blood pressure the urinary excretion of free norepinephrine was more significantly elevated than that of epinephrine. The urinary excretion of free epinephrine was more enhanced in patients with myocardial infarction complicated by disturbances in cardiac rhythm. The results suggest a relationship between the clinical course of myocardial infarction and the activity of the sympathoadrenal system.

The urinary excretion of dopamine and homovanillic acid was investigated in 20 patients with acute myocardial infarction. The mean excretion of dopamine was increased during the first five days of the disease. The mean excretion of the metabolite of dopamine—homovanillic acid was also higher during the first days of myocardial infarction than in the subsequent period, although it did not exceed the upper limit of normal. No significant correlation between urinary dopamine and noradrenaline excretion was found. The results of the study are discussed in the light of the augmented sympathetic activity accompanying acute myocardial infarction.

Summary Carbohydrate metabolism was studied in 47 atherosclerotic patients and 35 healthy subjects. A response to the glucose tolerance test corresponding to ℬprediabetesℭ as described by CONN was observed in the atherosclerotic patients, who also exhibited higher fasting ketone-body levels. Within the atherosclerotic group, abnormal glucose tolerance curves were given by overweight patients, but no relationship between the character of the glucose tolerance curve and either age or cholesterol level was observed. Cortisone administration induced diminished glucose tolerance in atherosclerotic patients. After cortisone, the ketone-body level remained high following ingestion of glucose. The glucose tolerance curve after insulin administration, and the serum nonesterified fatty acids (NEFA) curve after glucose and insulin, were for normal and atherosclerotic subjects virtually identical.

1. Ten patients with essential hypertension and ten healthy men were submitted to mental stress consisting of Kraepelin's arithmetic test combined with noise. Concentrations of plasma and urine catecholamines and of their metabolites as well as plasma renin activity before and after the test were studied. 2. In both groups a significant increase of noradrenaline and adrenaline in blood and noradrenaline in urine was observed. The urinary excretion of dopamine fell significantly in both groups after stress. 3. After mental stress a significant increase in urinary excretion of 3-methoxy-4-hydroxyphenylglycol was observed in both groups. The excretion of vanillylmandelic acid decreased significantly only in healthy subjects. 4. The plasma renin activity rose significantly in both groups but the increase was more pronounced in healthy subjects.

Urinary excretion of dihydroxyphenylalanine (DOPA), dopamine and noradrenaline was studied in 36 patients with acute myocardial infarction. The group included 18 patients with uncomplicated myocardial infarction and 18 patients with infarction complicated by heart failure and/or cardiac arrhythmias. Two patients died during hospitalization. The excretion of DOPA was higher in patients with myocardial infarction than in the control group. The increase was greater in uncomplicated infarction than in infarction with a complicated clinical course. In contrast, the urinary excretion of dopamine and noradrenalin was higher in complicated infarction. The possible causes of different behaviour of DOPA and catecholamines in relation to the clinical course of myocardial infarction are discussed.

Urinary excretion of catecholamines, vanillylmandelic acid, and methoxycatecholamines was studied in 50 patients with renovascular hypertension. The urinary excretion of noradrenaline was increased in patients with elevated peripheral plasma renin activity and in those with elevated renal vein renin ratio in comparison with the patients with normal plasma renin activity. The urinary excretion of dopamine was diminished and vanillylmandelic acid increased in the entire group of patients with renovascular hypertension. In the investigated group, following sodium restriction, the mean urinary excretion of noradrenaline increased while dopamine excretion decreased. These results suggest that the increased sympathetic activity may play a role in the pathogenesis of renovascular hypertension.

In view of the possible role of prostaglandins /PG/ in the pathogenesis of hypertension we have determined PGE2 and PGF2 alpha levels simultaneously with plasma renin activity/PRA/ in renal venous and caval venous blood in 13 patients with unilateral renal artery stenosis/RAS/ and in six untreated patients with unilateral parenchymal renal disease/PRD/. Four patients with essential hypertension were the control group. PG levels and PRA were estimated by RIA. In patients with RAS the mean PGE2 level as well as PRA was higher on the side of the stenosis. No such difference was found in the PGF2 alpha level. There was a significant correlation between the renal vein PGE2 ratio and renin ratio /stenotic side versus contralateral side/ r=0.520, 0.02 less than p less than 0.05. In patients with PRD prostaglandin levels in venous blood of the affected kidney were similar to that of venous caval blood, but markedly elevated in the venous blood of the contralateral kidney. PRA was similar on both sides. The data obtained in this study indicate, that prostaglandins in renal venous blood behave differently in hypertensive patients with RAS and PRD. In patients with RAS augmented PGE2 release may serve as a protective mechanism. In patients with PRD, the increased PG level in the non-affected kidney may reflect a compensatory mechanism in spite of the atrophic process in the affected kidney.

Urinary excretion of 3-methoxy-4-hydroxyphenylglycol (MHPG), noradrenaline, adrenaline and vanillylmandelic acid (VMA) was studied in 30 patients with acute myocardial infarction. The excretion of MHPG was higher in Patients with myocardial infarction than in the control group, with no difference between uncomplicated and complicated courses of the disease. The excretion of MHPG showed a negative although not significant correlation with noradrenaline and VMA during the first days of infarction and a statistically significant positive correlation on the 5th day of the disease. The possible causes of the changes observed are discussed.