Long-term results and complications of the syringopleural shunting for treatment of syringomyelia: a clinical study.

BACKGROUND: The use of drains in the treatment of syringomyelia has a simple and immediate appeal. Syringopleural shunting in syringomyelia has produced good short-term results, but limited information is available on long-term effects. We analyzed the complications and long-term outcomes after syringopleural shunting for syringomyelia. CLINICAL MATERIAL AND METHODS: Fourthy-four patients with large-sized syringomyelia underwent syringopleural shunting because of spinal cord compression between 1992 and 2010 in our clinic. Thirty-two patients had Chiari malformation type I (Group B), and 12 patients were associated with primary parenchymal cavitations (Group A). Their ages ranged from 14 to 71 years. Both craniovertebral decompression and syringopleural shunting were performed on 21 patients, whereas only syringopleural shunting was performed on another 21 patients. RESULTS: The follow-up period ranged from 1 year to 17 years (mean: 9.1 years). There was no operative mortality. Early postoperative MRI revealed that syringes of 43 patients had collapsed. There were 9 (20.5%) minor complications in 9 patients, including temporary neurological deficits (6), respiratory distress (2) and headache (1). Seven (15.9%) serious complications [permanent neurological deficit (1), shunt migration (2), shunt misplacement (1), spinal instability (1), tethering (1), CSF over drainage (1)] were seen in five patients. Four of them were treated with a secondary operation. Three patients (3/9; 33.3%) who were treated by syringopleural shunt alone (Group B2) required craniovertebral decompression, although the shunt was functional. During long-term follow-up, three patients stabilized, five patients (11.3%) developed a worse neurological condition, and two of these patients died 10 and 7 years after surgery. Of all patients, 88.6% showed significant clinical improvement. CONCLUSIONS: Although there were complications and failures, syringopleural shunting produced satisfactory results at long-term follow-up.

Ambulatory monitoring of blood pressure (AMBP) in patients with primary hyperparathyroidism.

The purpose of our study was to evaluate the behaviour of blood pressure (BP) by ambulatory monitoring of blood pressure (AMBP) in 53 patients with primary hyperparathyroidism (PHPT) compared to 100 essential hypertensive (EH) and 31 healthy subjects (HS). The correlations between calcium-phosphorus metabolism and haemodynamic parameters in all groups are included in the study. AMBP was performed using the oscillometric technique (Space-Labs, 90207, Redmond, WA, USA) and the following AMBP parameters were evaluated: average day time systolic (S) and diastolic (D) blood pressure (BP) and heart rate (HR) (when awake), average night time SBP, DBP and HR (when asleep) and average 24-h-SBP, DBP and HR. The definition of 'dipper' or 'non-dipper' subjects was established if night time SBP and DBP fall was >10% and <10%, respectively. In total, 25 PHPT patients (47.2%) were hypertensive (HT-PHPT) and 28 PHPT (52.8%) were normotensive (NT-PHPT). Mean 24-h-SBP and DBP obtained by AMBP was higher in HT-PHPT (P < 0.05) and EH (P < 0.05) than in NT-PHPT and HS. The multiple linear regression has shown that in PHPT-HT patients ionized calcium is an independent factor for the rise of 24-h-DBP values (r: 0.497; P < 0.05) and daytime DBP values (r: 0.497; P < 0.05). In 56% of HT-PHPT patients there is an absence of physiological BP nocturnal fall ('non-dipper'), which is statistically significant (P < 0.05) compared with 'non-dipper' EH patients (30%). In conclusion, in our study the prevalence of hypertension in PHPT was 47%. AMBP revealed that the 'non-dipping 'pattern was much higher in HT-PHPT patients in respect to EH patients.

High plasma levels of endothelin-1 in untreated Addison's disease.

The aim of this study has been to investigate the plasma endothelin-1 (ET-1) levels in adult patients with proven Addison's disease (AD). Plasma ET-1 levels were measured in 29 subjects (17 males and 12 females, aged between 20 and 54 years): 15 of them were patients with AD and 14 were sex- and age-matched normal subjects, used as a control group. All patients with AD have been studied under basal conditions and nine of them also after 2 weeks on oral corticosteroid therapy (individual cortisol dosage ranging from 25 to 37.5 mg/day and 0.1 mg/day 9 alpha-fluorohydrocortisone). Extracted plasma ET-1 was determined by a specific radioimmunoassay using rabbit endothelin antisera. Mean ET-1 values in the patients with AD were three times higher than in normal subjects (21.09 +/- 4.38 pg/ml vs 6.72 +/- 1.74 pg/ml; p < 0.0001). Plasma ET-1 levels assayed in the patients with AD after 2 weeks of corticosteroid therapy were significantly decreased (14.47 +/- 3.7 pg/ml vs 22.8 +/- 5.2 pg/ml; -37%; p < 0.001) compared to values in untreated patients. However, the plasma ET-1 values obtained following corticosteroid therapy were still significantly higher (p < 0.001) than those detected in the control subjects. These results clearly indicate that patients with untreated AD have increased circulating ET-1 levels that may be reduced by short-term corticosteroid therapy.

Increased plasma levels of endothelin-1 in patients with hyperthyroidism.

Plasma concentrations of endothelin-1 (ET-1) were measured in 25 hyperthyroid subjects, 15 hypothyroid subjects, and 21 age-matched normal controls. In hyperthyroid patients, plasma concentrations of ET-1 were significantly higher than in the control group (P < .0001) and in hypothyroid patients (P < .0001). In contrast, no differences were found between hypothyroid patients and controls. Plasma levels of ET-1 were similarly elevated as in patients with Graves' disease and those with toxic adenoma. No correlations were found between plasma ET-1 levels, thyroid hormones, and thyrotropin (TSH) in hyperthyroid, hypothyroid, and euthyroid groups. The results of our study clearly indicate that in hyperthyroidism, circulating levels of ET-1 are strongly increased, although the pathogenesis of the increase is unclear.

Circulating adrenomedullin is increased in patients with corticotropin-dependent Cushing's syndrome due to pituitary adenoma.

It has been demonstrated that adrenomedullin, a newly discovered peptide with structural similarity to calcitonin gene-related peptide (CGRP), is expressed in pituitary gland and affects basal and corticotropin (ACTH)-releasing factor (CRF)-stimulated ACTH release in animals, thus suggesting its potential role in regulating the hypothalamus-pituitary-adrenal axis. To evaluate whether ACTH and cortisol levels affect adrenomedullin production in humans, we studied 14 patients with Cushing's syndrome due to pituitary adenoma and 8 patients with Cushing's syndrome due to adrenal tumor, with measurement of circulating adrenomedullin by a specific radioimmunoassay (RIA). Adrenomedullin concentrations were significantly higher in patients with pituitary adenoma (37.6 +/- 17.8 pg/mL) versus controls (13.7 +/- 6.1 pg/mL) and patients with adrenal adenoma (17.8 +/- 2.2 pg/mL). After pituitary surgical treatment, plasma adrenomedullin decreased significantly. In one patient with Cushing's syndrome due to pituitary adenoma who underwent simultaneous sampling of the inferior petrosal venous sinuses, the adrenomedullin concentration was significantly higher in plasma collected from the side with the adenoma and increased after CRF administration (delta increase, 42.6%), according to ACTH levels. Our findings indicate that circulating adrenomedullin is increased in Cushing's disease, and the pituitary gland may represent the site of the elevated production of adrenomedullin in this condition.

Plasma endothelin-1 levels in normotensive and borderline hypertensive subjects during a standard cold pressor test.

Endothelin-1 (ET-1) is a potent vasoconstrictor peptide derived from endothelium. The presence of ET-1 in human vascular endothelium and in the plasma suggests that it may play a role in the regulation of vascular tone and blood pressure (BP) in humans. The aim of this study was to evaluate the behaviour of plasma ET-1 in 10 normotensives (average 36.3 +/- 14.8 years) and 10 borderline hypertensives (average 42.0 +/- 11.7 years) before, during and after a standard cold pressor test. We also evaluated the behaviour of heart rate and BP at the same time. Our results demonstrated that the baseline (-10 and 0 min) plasma ET-1 values were identical for the two groups (8.6 +/- 5.8 and 8 +/- 4.7 pg/ml in normotensives; 7.8 +/- 2.7 and 7 +/- 2.4 pg/ml in borderline hypertensives). A statistically significant increment was verified 10 min after exposure to cold in the borderline hypertensive group (12.1 +/- 5.1 pg/ml) compared with the normotensives group (6.8 +/- 4.5 pg/ml; P < 0.05). In conclusion, our study demonstrated that after 10 min of cold pressor stimulus an increase of circulating ET-1 levels was seen in borderline hypertensives.

High plasma endothelin-1 levels in hypertensive patients with low-renin essential hypertension.

Endothelin-1 (ET-1) is a potent vasoconstrictor peptide derived from endothelial cells and may be important in the control of systemic blood pressure (BP) and local blood flow. Immunoreactive ET-1 plasma levels may be normal or elevated in human arterial hypertension, although the exact pathophysiological role of ET-1 remains to be established. The aim of our study was to determine the relationship between the components of the renin-angiotensin-aldosterone system and plasma ET-1 levels in patients with low, normal or high-renin essential hypertension. The study groups included 13 patients with low-renin essential hypertension (average age 43.5 +/- 16.2 years), 16 patients with normal-renin essential hypertension (46.5 +/- 13.4 years), 11 patients with high-renin essential hypertension (40.7 +/- 13.8 years) and 12 healthy subjects (43.1 +/- 11.4 years). Our results demonstrated that the mean ET-1 values of all patients with essential hypertension were 10.4 +/- 3.4 pg/ml; there was not a statistical correlation between plasma renin activity (PRA) and the ET-1 levels of hypertensives; instead there was a statistically significant correlation between plasma ET-1 and plasma aldosterone (PA) (r = 0.393; P < 0.026). In particular mean plasma ET-1 values in patients with low-renin essential hypertension (12.6 +/- 2.1 pg/ml) were significantly higher (ANOVA = 0.000, P < 0.05) than those of normotensive subjects (7.7 +/- 1.7 pg/ml), patients with normal-renin essential hypertension (8.5 +/- 2.8 pg/ml), and patients with high-renin essential hypertension (9.9 +/- 3.8 pg/ml), respectively. There was a statistical correlation between PA and ET-1 levels in patients with low-renin essential hypertension (r = 0.619, P < 0.024). Our study demonstrated that there was an increase of circulating ET-1 levels in patients with low-renin essential hypertension and ET-1 plasma levels correlated with PA. The results suggest that ET-1 may play an important role in this particular form of human essential hypertension.

Adrenomedullin and endocrine disorders.

Adrenomedullin (AM) is a recently discovered potent vasodilatory peptide, originally isolated in extracts of human pheochromocytoma, with activities including maintenance of cardiovascular and renal homeostasis through vasodilatation, diuresis and natriuresis. Human AM consists of 52 amino acids with a 6-member ring structure linked by a disulfide bond and amidated COOH terminal, which belongs to calcitonin gene-related peptide (CGRP) and amylin. The main sites of AM production are the lungs, vascular tissues (both endothelial and smooth muscle cells), heart, kidney, adrenal glands, pancreatic islets, placenta, anterior pituitary gland and gastrointestinal neuroendocrine system. Intravenous injection of AM increases blood flow predominantly in the tissues with the highest AM expression, suggesting that AM functions primarily as a paracrine/autocrine hormone, but it is also important as circulating hormone. The objective of this review is to analyze the evidence that AM may play a role in some endocrine disorders.

Plasma levels of endothelin-1 increase in patients with sarcoidosis and fall after disease remission.

BACKGROUND: Sarcoidosis is a chronic systemic disease, characterized by an imbalance of immunity processes and the presence of granuloma. Endothelin-1, a new vasoactive and bronchoconstrictive peptide, is a powerful mitogen for smooth muscle cells and fibroblasts and plays a role in the inflammation state. We postulate that endothelin-1 has a role in sarcoidosis. METHODS: We studied the behaviour of circulating levels of endothelin-1 in 20 patients with sarcoidosis and its correlation with some biochemical parameters of activity disease, such as erythrocyte sedimentation rate (ESR) and serum angiotensin-converting enzyme (SACE). We measured serum levels of ESR, SACE, calcium and plasma endothelin-1 levels in all patients at the beginning of the study and one again in 9 patients with clinical-biochemical remission of disease after steroid treatment. RESULTS: In patients with sarcoidosis, circulating levels of endothelin-1, SACE and ESR were significantly higher (p<0.001) than those of healthy subjects. Moreover, in patients with pulmonary involvement, there was a significant statistical difference (p<0.001) between endothelin-1 levels and radiological stage compared to normal subjects. In the 9 patients with remission of disease, both endothelin-1 levels and parameters of activity disease normalized. CONCLUSIONS: Our results seem to suggest that the increase of plasma endothelin-1 levels in active sarcoidosis can represent an expression of the endothelial dysfunction and reflect the picture of cellular activation.

A chronobiological approach to circulating levels of renin, angiotensin-converting enzyme, aldosterone, ACTH, and cortisol in Addison's disease.

This study deals with a chronobiological approach to the circadian rhythm of the renin-angiotensin-aldosterone system (RAAS) and the ACTH-cortisol axis (ACA) in patients with Addison's disease (PAD). The aim is to explore the mechanism(s) for which the circadian rhythmicity of the RAAS and ACA takes place. The study has shown that both the RAAS and ACA are devoid of a circadian rhythm in PAD. The lack of rhythmicity for renin and ACTH provides indirect evidence that their rhythmic secretion is in some way related to the circadian oscillation of aldosterone and cortisol. This implies a new concept: a positive feedback may be included among the mechanisms which chronoregulate the RAAS and ACA.

[Serum activity of angiotensin-converting enzyme and osteocalcin levels in hyperthyroidism]. / L'attività sierica dell'enzima di conversione dell'angiotensina ed i livelli di osteocalcina nell'ipertiroidismo.

This study was carried out in order to investigate serum changes of osteocalcin (BGP) and angiotensin converting enzyme (SACE) activity in a group of patients with hyperthyroidism. We studied 20 hyperthyroid patients (F 14, M 6; age mean 37.5 +/- 16.8 years) and 13 control subjects (F 11, M 2; age mean 40.3 +/- 7.5 years). In both patients and controls we measured: FT3, FT4, T3, T4, TSH, BGP, SACE. Finally, in patients with hyperthyroidism a TRH test and functional investigations were also performed. We observed that mean SACE levels were significantly increased in hyperthyroid patients (32.06 +/- 10.3 nmol/ml/min) in respect to control subjects (14.66 +/- 3.88 nmol/ml/min) (p = 2.02 E-6). Similarly serum BGP levels were significantly increased in hyperthyroid patients (5.94 +/- 2.55 ng/ml) than in control subjects (2.89 +/- 1.58 ng/ml) (p = 5.66 E-4). There was a significant linear correlation between SACE and T4 levels (r = 0.48; p < 0.05), between serum BGP and T4 (r = 0.50; p < 0.02) and furthermore between SACE and BGP (r = 0.57; p < 0.01). In conclusion both serum BGP and SACE levels are increased in patients with hyperthyroidism and are directly correlated between than and with indexes of thyroid function; therefore, they may be regarded as peripheral indexes of hyperthyroidism.

Amlodipine in ambulatory hypertensive patients: humoral and haemodynamic effects.

In order to evaluate the mid-term effects of amlodipine, a 1,4-dihydropyridine calcium antagonist, as well as its effects on the renin-angiotensin-aldosterone system (RAAS), on water and electrolyte balance, on urinary excretion of albumin (UAE) and on lipid metabolism, thirteen hypertensive patients (2 M, 11 F, mean age 54 years) were studied in the course of 24 weeks of therapy with amlodipine at 5-10 mg/day. Pre-therapy and periodically during therapy, the systolic blood pressure (SBP), diastolic blood pressure (DBP) and heart rate (HR) were recorded in the sitting orthostatic positions (2 measurements). Laboratory tests were performed at times O and at 24 wks with the patients fasting for at least 12 h in the recumbent position. The tests included: plasma renin activity (PRA), plasma aldosterone (PA), serum angiotensin converting enzyme (SACE), blood urea nitrogen (BUN), blood creatinine, plasma electrolytes (Na, K, Cl), triglycerides, total cholesterol (TC) and HDL-cholesterol (HDLC), along with 24-h urine samples (with sterile urine) to determine UAE. The results of this study demonstrate that SBP, DBP and HR were significantly reduced during the 24 wks of therapy. The water and electrolyte and renal function were not modified. After treatment the levels of TC were significantly reduced. No change was observed in the RAAS, while the mean levels of UAE were reduced though not significantly. In conclusion, amlodipine was shown to be effective for the therapy of hypertension; it does not cause reflex tachycardia even in mid-term therapy and was effective in reducing TC levels.

Dynamic exercise induces elevation of plasma levels of endothelin-1 in patients with coronary artery disease.

In this investigation the response of endothelin-1 plasma levels to dynamic exercise in patients with coronary artery disease (CAD) was studied. The study population consisted of 20 patients with CAD, 16 men and 4 women (mean age 53 +/- 8.6 years). Seven normal volunteers all men (mean age 53.4 +/- 4.4 years) were studied as a control group. Seven patients had prior myocardial infarction. All patients and controls exercised on a multi-stage bicycle ergometer; plasma endothelin-1 levels and hemodynamic indices were measured at rest, at peak exercise, and at two and six minutes after exercise. Of the 20 patients examined, 7 (35%) showed electrocardiogrpahic (ECG) signs of myocardial ischemia during the stress test. The mean plasma endothelin-1 concentration increased significantly from 7.8 +/- 3.0 to 13.6 +/- 3.5 pg/mL at exercise peak (P < 0.05) only in patients who did not show ECG signs of myocardial ischemia and returned to baseline values during recovery (six minutes) (9.4 +/- 2.1 pg/mL). In normal subjects baseline endothelin-1 levels (9.4 +/- 4.2 pg/mL) were not significantly altered at peak exercise (10.8 +/- 4.7 pg/mL) and at recovery (11.3 +/- 3.6 pg/mL). The hemodynamic parameters were not correlated with the plasma endothelin-1 levels before, during, and after exercise in all groups. The present study demonstrated that the plasma levels of endothelin-1 in patients with CAD increased significantly during stress testing.

beta-Endorphin and propiomelanocortin-correlates peptides response in suspected and confirmed ischemic heart disease during exercise.

UNLABELLED: In this study, we investigated circulating beta-endorphin, ACTH and cortisol in subjects with suspected coronary artery disease (CAD) and in patients with CAD during stress testing. Group I: 18 subjects, all male (average age 48 +/- 9 yrs) with suspected (CAD) were enrolled. Group II: 35 patients, 30 males and 5 females (average age 54.3 +/- 7 yrs) with CAD, were enrolled. Ten patients had previous myocardial infarction. In all patients that underwent coronarography a stenosis > 75% was found in at least one coronary artery. The stress test was performed with a cycloergometer, increasing work loads 25 watt every 2 min. All subjects and patients were in the recumbent position for at least 30 minutes prior to testing. During this period a 3-way catheter was placed in the antecubital vein and blood was drawn for Beta-endorphin, ACTH and cortisol; additional blood samples were drawn using a pre-chilled syringe at maximum effort and during the recovery period. RESULTS: group I: 9 of the subjects with suspected CAD had either ECG or clinical signs of ischemic during the stress test. In subjects with a negative test, the test was carried out for a longer period of time and at a higher work load. There was an increase in Beta-endorphin and ACTH at peak exercise and during recovery. Plasma cortisol increase during the period of recovery. Group II: 16 of the 35 patients with CAD exhibited ECG signs of induced myocardial ischemia; there was no difference in work loads in patients with positive or negative stress test. Exercise time was reduced in all patients and plasma Beta-endorphin increased at peak exercise and recovery in patients with a negative stress test. In conclusion our study revealed a different response of Beta-endorphin, ACTH and cortisol plasma levels in subjects with suspected CAD and in patients with CAD during exercise testing.

Plasma endothelin-1 concentrations in patients with coronary artery disease during stress test before and after nisoldipine administration.

The purpose of this study was to determine the response of plasma levels of endothelin-1 (ET-1) to dynamic exercise in patients with coronary artery disease and chronic stable angina pectoris and positive exercise tolerance test, before and after treatment with the calcium antagonist nisoldipine (20 mg/day buccally for 7 days). Plasma ET-1 levels and hemodynamic parameters (blood pressure and heart rate) were determined at rest, at peak exercise and recovery. All patients had a positive electrically and clinically stress test and all of the eight patients did not developed ECG signs of myocardial ischemia after nisoldipine administration. Before nisoldipine treatment the plasma ET-1 levels did not increase significantly during exercise. After nisoldipine treatment the plasma ET-1 levels were significantly lower at rest and during exercise compared with those revealed before calcium antagonist treatment. In conclusion our results suggest that in patients with chronic stable angina pectoris the treatment with calcium antagonist nisoldipine reduced ischemia and plasma ET-1 levels.

Serum angiotensin converting enzyme in diabetic retinopathy.

Serum levels of angiotensin converting enzyme (SACE) were measured in 118 diabetic patients divided into the following four groups: 44 insulin-treated diabetic patients with severe retinopathy, 38 non insulin-treated diabetic patients with severe retinopathy, 18 diabetic patients, including both insulin-treated and non insulin-treated subjects with background retinopathy, 18 diabetic patients, insulin-treated and non insulin-treated without signs of retinopathy. Nineteen retinopathic patients non diabetic were also studied in order to verify whether SACE levels are altered when retinopathy is present independently from diabetes. The control group was composed of 44 normal subjects. When the data from the above six groups of subjects were submitted to statistical tests (one-way ANOVA, T-test of Bonferroni and test of Student-Newman-Keuls), the study yielded the following results: i) a remarkable difference between the SACE levels in healthy subjects and those in the three groups of diabetic retinopathic patients considered; ii) a non statistically significant difference of SACE levels between normal subjects and diabetic patients without retinopathy; iii) a non statistically significant comparison of SACE levels of normal subjects versus non diabetic retinopathic patients. Therefore, we concluded that while primitive diseases of the retina are not associated with an increase of SACE levels, yet when diabetes and retinopathy coexist, the SACE levels increase remarkably (in rather an independent way from the type of diabetes, the age of subjects, the stage of retinal disease and the daily average insulin dose), suggesting that most of the enzyme's increase originates from the endothelium of peripheral vasa, widely involved in most of the retinopathic diabetic patients.

[The behavior of serum angiotensin-converting enzyme in normotensive subjects, in subjects with essential hypertension and in subjects with primary hyperaldosteronism on the orthostatic test]. / Il comportamento del serum angiotensin converting enzyme in soggetti normotesi ed in soggetti con ipertensione essenziale ed in soggetti con iperaldosteronismo primario alla prova dell'ortostatismo.

The results of this study demonstrate that only in healthy normotensive subjects during extended orthostatism that the renin-angiotensin-aldosterone system remains integral and is characterized by a significant increase in serum angiotensin-converting enzyme (SACE), plasma renin activity (PRA) and plasma aldosterone (PA). SACE modification do not seems to directly follow that of PRA (as shown by the absence of a direct correlation between SACE and PRA). In essential hypertension, the behavior of SACE seems to change, without demonstrating a significant increase in the mean levels of this enzyme. Finally in hypertension of known origin, such as primary hyperaldosteronism, the low levels of SACE in the recumbent position (not stimulated by orthostatism) seem to depend (by mechanism of negative biofeedback) on the increased serum levels of PA, which is moreover verified in the same group for PRA.

Plasma adrenomedullin concentrations in patients with renovascular or malignant hypertension.

AIM: The aim of the present study was to investigate the behaviour of plasma adrenomedullin (AM), a hypotensive peptide, in patients with malignant (MHT) and renovascular hypertension (RVH), 2 pathologic conditions in which renin-angiotensin system (RAS) is activated and to compare them with those in essential hypertensive patients (EHT) and normotensive subjects (NS). METHODS: Three groups of hypertensive patients have been studied: group 1 (4 patients with MHT), group 2 (10 patients with RVH), group 3 (24 patients with EHT) and 21 patients NS were enrolled as controls. In all patients, 10 ml vein blood samples were collected and AM was measured with specific radioimmunoassay. RESULTS: As expected, the plasma renin activity (PRA) levels in the RVH and MHT patients were significantly higher (p<0.0001) respect to NS and EHT. The mean plasma AM (+/-SD) concentrations in EHT (22.5+/-9.1 pg/ml) and RVH (46.8+/-19.4 pg/ml) were significantly (p<0.0001) higher than those in NS (13.7+/-6.1 pg/ml). The plasma AM concentrations were further elevated in MHT patients (107+/-12.3 pg/ml) and were significantly higher (p<0.0001) than those in EHT and RVH patients. In the MHT patients the elevated plasma AM levels, similarly to blood pressure and PRA values, declined after antihypertensive treatment (36.8+/-5.7 pg/ml; p<0.01). CONCLUSION: In conclusion, the findings demonstrated that the plasma AM concentrations were increased in proportion to the severity of arterial hypertension. RAS was activated in patients with MHT and RVH suggesting that activation of this system may contribute to increased in the plasma levels of AM.

Endothelin-1 circulating levels increase in patients with orthotopic heart transplantation and in chronic therapy with cyclosporine.

BACKGROUND: The aim of the study was to investigate the behaviour of plasma levels of endothelin-1 (ET-1), an endothelial peptide with vasoconstrictive and proliferative actions, in patients with cardiac transplantation and in chronic treatment with cyclosporine A, some of whom became hypertensive after cardiac transplantation. METHODS: We studied: 1) 18 consecutive patients (15 M, 3F; mean age 53 +/- 7 yrs) who underwent cardiac transplantation about six months ago at least (range 6-108 months); 2) 15 patients with essential arterial hypertension (10 M, 5 F; mean age 42 +/- 15 yrs) without organ damage; 3) 21 normal subjects (15 M, 6 F; mean age 31 +/- 12 yrs). Plasma levels of ET-1 (RIA), haemodynamic and functional renal parameters were determined in all groups and plasma levels of cyclosporine were measured in patients with cardiac transplantation. RESULTS: ET-1 was higher in patients with cardiac transplantation than in the other two groups (p < 0.05); instead there was no difference between patients with essential arterial hypertension and controls (p>0.05). A statistical difference was found between circulating ET-1 in hypertensive transplanted patients. In heart transplanted patients a positive and significative correlation was found between plasma levels of ET-1 and systolic (r=0.525; p<0.037) blood pressure.

Response of serum angiotensin converting enzyme, plasma renin activity and plasma aldosterone to conventional dialysis in patients on chronic haemodialysis.

The aim of this study was to examine serum angiotensin converting enzyme (SACE) activity and the renin-angiotensin-aldosterone system in patients on chronic haemodialysis during one routine dialysis session. Fourteen patients (8 men and 6 women; mean age 51.9 +/- 17 years) with end stage renal disease, receiving regular haemodialysis treatment for an average of 6 months, were studied. The patients were dialysed for 4 hours three times a week using cellulose membranes (cuprophan). After an overnight fast blood samples were taken from the patients before and after the haemodialysis session. Serum and plasma were separated and stored at -20 degrees C until assayed for SACE, plasma renin activity (PRA) and plasma aldosterone (PA). For comparison, SACE, PRA and PA were also measured in 8 patients after renal allotransplantation and on treatment with cyclosporin A (5 men, 3 women; mean age 38.9 +/- 12.3 years) and in 19 healthy subjects (13 men, 6 women; mean age 38.9 +/- 12.3 years). SACE levels in patients with chronic renal failure and on haemodialysis (17.55 +/- 9.03 nmol/ml/min) and in patients with renal transplantation (18.12 +/- 3.92) were significantly higher than those of the healthy subjects (9.27 +/- 1.67) (p < 0.0001, respectively). At the end of the dialysis session SACE levels in patients with chronic renal failure (14.9 +/- 7.19) did not increase in respect to pre-dialysis levels (17.55 +/- 9.03; p = 0.132). PRA and PA values increased after the dialysis session (p < 0.026 and p < 0.044, respectively). Correlation of SACE with PRA and PA was not demonstrated before or after the dialysis session. In patients with chronic renal failure and on haemodialysis our findings suggest that a disarrangement exists between the circulatory components of the reninangiotensin-aldosterone system before and after the dialysis session.