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Biomedical subjects

V P Masenko

Publications and source records attributed to V P Masenko.

At least 19 recordsLinked to original sources
PubMed2000

Active immunization against endothelin-1 is associated with a decrease in plasma endothelin-1 and changes in vascular reactivity.

Exogenous endothelin-1 (ET-1) or high concentrations of the peptide in pathological conditions have marked effects on vascular reactivity. In order to evaluate the role of endogenous ET-1 we investigated responsiveness of conduit (aorta) and of resistant-like (tail artery) vessels in ET-1-deficient rats. Elimination of circulating ET-1 was achieved by active immunization of Wistar rats with a peptide-haemocyanin conjugate (anti-ET-1 group), leading to a marked reduction in plasma level of the peptide in comparison with that of vehicle-treated animals (control group): 1.9 fmol/ml vs 4.9 fmol/ml, respectively. The immunization was associated with a slight elevation of mean arterial pressure, whereas heart rate remained unchanged. In the anti-ET-1 group rings of isolated aorta displayed reduced sensitivity to ET-1: EC50 = 6.57 nM vs 2.95 nM in the control group. Tail arteries of the ET-1-deficient rats showed diminished responses to ET-1, the maximal rise in perfusion pressure: +5.2 mmHg vs +13.6 mmHg in the control group. After immunization, rings of isolated aorta displayed no changes in endothelium-dependent relaxation to acetylcholine (Ach, EC50 = 0.20 microM vs 0.35 microM in the control group), whereas experiments on perfused tail artery showed a twofold reduction in Ach effects. Thus, depletion of circulating ET-1 induces slight changes in haemodynamics associated with altered vessel responsiveness to vasoactive substances.

Acetylcholine↗
PubMed2000

[Features of dopaminergic system function in menopausal females with arterial hypertension].

AIM: Assessment of dopaminergic activity by changes in urine excretion of dopamine, arterial hypertension, blood prolactine, 24-h diuresis and natriuresis in response to a single (2.5 mg) and 7-day (daily dose 5 mg) administration of parlodel in patients with essential hypertension (EH) in menopausal and reproductive age having different serum levels of estrogens. MATERIALS AND METHODS: The indices of 52 hypertensive menopausal women and of 18 women at reproductive age of whom 8 had hypothalamic syndrome were followed up. RESULTS: A single dose parlodel (bromocriptine) in the dose 2.5 mg 2 hours after its administration caused a significant fall in arterial pressure, rise in 24-h diuresis in hypertensive menopausal women (p < 0.01). Parlodel given in a daily dose 5 mg for 7 days in menopausal hypertensive women lowered a significant fall in arterial pressure, blood concentrations of aldosteron, prolactin, aroused dopamine and urinary sodium excretion (p < 0.01). Similar were the changes in hypertensive women at reproductive age with hypothalamic syndrome (n = 8). In such women free of hypothalamic impairment the changes did not occur (n = 10). A significant positive correlation was found between serum levels of prolactine and estradiol in all the hypertensive women in menopause. CONCLUSION: Deficiency of dopaminergic activity in menopause is induced by hypoestrogenemia correlating with serum levels of prolactin. This deficiency was identified in hypertensive menopausal women by the results of acute and prolonged tests with dopamine mimetic--parlodel.

Adult↗
PubMed2000

[Role of hypothalamo-hypophyseal-adrenal axis in the pathogenesis of arterial hypertension in patients with prolactinoma of the anterior lobe of the hypophysis].

AIM: To elucidate mechanisms underlying arterial hypertension (AH) in patients with hyperprolactinemia, prolactin-secreting adenoma of the anterior lobe of the hypothesis, in particular. MATERIAL AND METHODS: 9 females with microprolactin-secreting and 4 females with macroprolactin-secreting adenoma of the anterior lobe of the hypophysis (mean age 33.8 +/- 3.7 years) were examined using radioimmunoassay of the hormones, computed tomography, MR-tomography of the adrenals and brain. RESULTS: Humoral regulation of the hypothalamic-hypophyseal-adrenal axis was found different in patients with microadenoma due to dopaminergic insufficiency of the hypothalamus and in patients with macroadenoma--tumor of the hypophyseal genesis. Patients with microadenoma were diagnosed to have low-renin diastolic arterial hypertension with clinical symptoms of hyperaldosteronism and high levels of plasma aldosterone. Patients with macroadenoma had normal arterial pressure, aldosterone levels and plasma renin activity. Treatment with parlodel, agonist of dopaminergic receptors, reduced arterial pressure, prolactin level, plasma aldosterone and raised plasma renin activity in patients with microadenoma. Such changes were not observed in patients with macroadenoma. CONCLUSION: It is suggested that one of the causes of AH in patients with microprolactin-secreting hypophyseal adenoma lies in hyperaldosteronemia which develops as a result of dopaminergic insufficiency of the hypothalamus and hyperprolactinemia.

Adult↗
PubMed2000

[Redergin treatment of hypertensive menopausal women].

AIM: To assess a hypotensive effect of redergin (dihydroergotoxin)--agonist of dopaminergic receptors--in monotherapy (4.5-6 mg/day) and in combination with enalapril and amlodipin (10 mg/day). MATERIAL AND METHODS: Redergin in monotherapy or combined therapy was given to 106 hypertensive women in pre- or postmenopause and 24 hypertensive women of reproductive age. Antihypertensive effect was assessed by changes in arterial pressure, frequency and severity of hypertensive crises, diuresis, clinical symptoms of menopausal syndrome. RESULTS: A significant fall in arterial pressure, intensive diuresis, less frequent or absent hypertensive crises, relief of menopausal symptoms were observed on day 10-14 of redergin monotherapy of menopausal patients with mild hypertension and in combined treatment of menopausal women with moderate and severe hypertension. CONCLUSION: Antihypertensive and diuretic effect of redergin confirm a pathogenetic role of deficient dopaminergic activity in development of menopausal hypertension.

Adult↗
PubMed1999

[Levels of biologically active substances in the blood of patients resistant and nonresistant to antihypertensive therapy].

AIM: To clarify the role of differences in the levels of some biologically active substances (BAS) in plasma of patients with resistance to therapy or without it measured before treatment, during treatment and application of plasmapheresis. MATERIALS AND METHODS: Resistance to therapy was assessed clinically and according to 24-h monitoring in 35 patients aged 35-56 years with essential hypertension (n = 19), related to chronic pyelonephritis (n = 13) and glomerulonephritis (n = 3). Plasma BAS were studied by radio- and enzyme immunoassays. RESULTS: Blood pressure monitoring provided more precise determination of the treatment responders than clinical tests. Initially, responders to therapy had higher level of endothelin-1 and low of hydrocortisone. CONCLUSION: Responders to antihypertensive therapy were distinguished by a significant decrease of plasma aldosterone within a year vs aldosterone levels before the treatment. Nonresponders had no significant decrease of plasma aldosterone. No other marked differences in plasma BAS between the responders and nonresponders to antihypertensive treatment were found.

Adult↗
PubMed1998

[Clinical and biochemical features of atherosclerosis main risk factors in children of probands with primary hyperlipidemia].

AIM: Study of the incidence of hyperlipidemias and coronary atherosclerosis risk factors. MATERIALS AND METHODS: A clinical and biochemical study of 35 children (25 men and 10 women aged 6 to 27 years) from 30 families of probands with primary hyperlipoproteinemias (HLP) was carried out. Use of modified risk factors (RF) in the examined group permitted the detection of hypodynamia in 25 subjects, obesity in 4, alcohol abuse and tobacco smoking in 1, and disorders of lipid metabolism in 31 (88%) cases. RESULTS: Hypercholesterolemia was detected in 26 examinees, combined HLP in 1, hypoalphacholesterolemia in 3, and type V hyperlipoproteinemia in 1 case. The level of lipoprotein (a) was increased and positively correlated with xanthomatosis and the age of examinees. The level of basal immunoreactive insulin was within the normal range of values. Analysis of the relationship of this parameter and other coronary atherosclerosis RF revealed a correlation of the level of immunoreactive insulin and content of blood low-density lipoprotein cholesterol. In only 2 of the 30 examined families of probands with primary HLP there were no disorders of lipid metabolism and other modified RF. CONCLUSION: Children, adolescents, and young people from families with primary HLP represent a risk group; they are to be regularly examined in order to prevent coronary disease and atherosclerosis and to detect and treat it in time.

Adolescent↗
PubMed1998

[Activity of renin-angiotensin-aldosterone system (RAAS) and vasopressin level in patients with primary pulmonary hypertension].

AIM: Assessment of RAAS and vasopressin in patients with primary pulmonary hypertension (PPH). MATERIALS AND METHODS: Activity of plasma renin (APR), angiotensin-converting enzyme (ACE), plasma levels of angiotensin II (AII) and vasopressin (VP), serum concentration of aldosteron (AS) were measured by radioimmunoassay and enzyme immunoassay in 21 PPH patients with circulatory failure (age 34.7 +/- 2.1 years), 11 patients with NYHA functional class II-III, 10 with class IV, and 10 control subjects (age 29.8 +/- 1.5 years). RESULTS: Compared to controls, 21 PPH patients had elevated RAAS parameters: APR up to 3.52 ng/ml/h (p < 0.05), activity of ACE up to 43.13 units, AII level up to 33.93 ng/ml (p < 0.01), AS up to 468.86 ng/ml (p < 0.01), VP up to 5.26 ng/ml (p < 0.001). Circulatory failure progression resulted in activation of all the RAAS components. This and VP activation was the greatest in PPH patients with ACE > 5 ng/ml/h. PPH patients with mean pressure in the pulmonary artery higher than 60 mm Hg demonstrated higher ARP, AS, VP, AII, ACE than those who had this pressure under 60 mm Hg. CONCLUSION: PPH patients display a noticeable activation of RAAS and VP. This activation seems to be secondary as the changes increase with elevation of the pressure in the pulmonary artery and aggravation of circulatory insufficiency. Plasma renin activity determines the degree of RAAS activation as a whole. The discovered activation of RAAS in PPH gives grounds for doubts in the validity of using ACE inhibitors in the treatment of PPH.

Adolescent↗
PubMed1998

[The use of aspirin in patients with primary pulmonary hypertension].

AIM: To investigate aspirin efficacy in patients with primary pulmonary hypertension (PPH) after a course of prostaglandin E-1 (PE) treatment. MATERIALS AND METHODS: 12 PPH patients (mean age 35.7 +/- 2.5 years) having the disease for 6.7 +/- 1.1 years were assigned to a 6-month course of aspirin treatment in a dose 100 mg/day in combination with calcium antagonist isradipin. All the patients have previously undergone 21-day PE treatment (vasaprostan). Before and after the treatment, the patients were examined clinically and biochemically. RESULTS: As shown by ECG, chest x-ray, bicycle exercise, aspirin used in combination with isradipin led to stabilization of the disease. Platelet aggregation also remained stable, thromboxan B2 and endothelin-1 levels went down. Low doses of aspirin allowed to avoid side effects typical for this drug. CONCLUSION: Use of aspirin in a dose 100 mg/day in combination with calcium antagonists to treat primary pulmonary hypertension is justified.

Adult↗
PubMed1995

[Density of lymphocyte beta-2 adrenoreceptors in the course of hypertension].

Baseline density of intact lymphocyte beta2 adrenoreceptors (B max., 3H-DHA) was compared to dynamics of left ventricular hypertrophy (LVH) and frequency of essential hypertension (EH) complications within 7-9-year follow-up in 27 patients with EH stage II. No significant correlation was noted between B max and LVH changes. In a subgroup of 9 patients with initially very high B max overall number of complications reached 77.8% against 27.5%) (p<0.05) in control. These patients also developed acute myocardial infarctions more frequently (33.3% versus 0%, p<0.05). Such complications as strokes, coronary failure occurred with the same frequency. More extended trials are needed to infer on prognostic value of lymphocytic beta2-adrenoreceptor density.

Adult↗
PubMed1994

[Clinical and diagnostic value of prostaglandins E determination in patients with ulcer].

The authors investigate the relevance of ulcer clinical variants (recent ulcer, of 10 years history and 2-3 annual exacerbations, chronic ulcer with aggravations and incomplete remissions) to production of endogenic PGE by gastric mucosa and to blood PGE level. It is shown that with ulcer progression PGE synthesis activization is replaced by its inhibition. A reverse relationship appeared between gastric juice and blood PGE and duration of ulcer. Etiopathogenetic heterogeneity is suggested in the group with complicated ulcer.

Adult↗
PubMed1993

[Dynamics of prostaglandin E content in patients with duodenal ulcer various treatment regimens].

PGE levels were measured in duodenal ulcer patients treated by H2-blockers of histamine receptors of hyperbaric oxygenation (HBO). Histadyl is shown to cause a marked decrease in gastric juice PGE concentrations in contrast to HBO that raised PGE levels close to normal values. It is thought necessary to administer long-term maintenance therapy after cicatrisation of the ulcer lesion with the drugs improving local microcirculation and stimulating bicarbonates production in gastric mucosa, synthetic prostaglandins analogues, in particular.

Adult↗
PubMed1993

[The effect of obzidan monotherapy on the beta 2-adrenoreceptors of the lymphocyte adenylate cyclase system in hypertension patients].

Obsidan (propranolol) monotherapy was investigated for the effect on the density of lymphocytic beta2-adrenoreceptors (B max), the activity of lymphocytic homogenates adenylate cyclase (AC), plasma renin activity (PRA), aldosterone concentration (A) and plasma catecholamines (CA). Obsidan treatment brought about a 40% increase in B max without a significant changes in AC activity. Contrary to a significant fall in PRA, A and norepinephrine in plasma reduced insignificantly. Changes in B max correlated with its baseline level (r = -0.56, p < 0.01), PRA (r = 0.57, p < 0.01) and A level in plasma (r = 0.62, p < 0.01). No significant correlations appeared between hypotensive effect of the drug and drug-related changes in B max and AC activity, while PRA and A concentrations showed such dependence. B max and before treatment mass of the left ventricular myocardium correlated significantly (r = = 0.595, p < 0.01). A small decrease in the myocardial mass followed obsidan administration, being related to B max (r = = 0.497, p < 0.05). It is concluded that obsidan-induced changes in lymphocytic beta 2-adrenoreceptors correlate with alterations in the activity of renin-angiotensin-aldosterone system and myocardial hypertrophy dynamics.

Adenylyl Cyclases↗
PubMed1993

[The humoral immunity indices and vascular reactivity of patients with hypertension and an elevated blood lipid level].

Out of 60 males aged 41 +/- 1 suffering from mild arterial hypertension (158 +/- 4/100 +/- 2 mm Hg) a hereditary load by hypertension was found in 63.3%, serum cholesterol levels reached 200 mg/dl in 85% of the patients. The patients with the load and enhanced Na-Li countertransport (403 +/- 49 mumol Li/1/cell/hr against 185 +/- 28 mumol Li/1/cell/hr in those without hereditary predisposition, p < 0.05) showed a significantly higher serum level of IgA and IgE (3.68 +/- 0.33 g/l and 127 +/- 14 U/ml vs 2.61 +/- 0.33 g/l and 79 +/- 15 U/ml, respectively, in those without the load, p < 0.01, p < 0.05). An IgE level significantly correlated with the amplitude of norepinephrine vascular reactivity (r = 0.35, p < 0.05). The discussion is concerned with IgE hyperproduction significance. Correlating with the amplitude of vascular reactivity on sympathetic stimuli and being independent of hypertension magnitude, this hyperproduction may underlie a high risk of atherosclerosis and vascular complications as a result of IgE-mediated vascular reactions in young subjects with mild hypertension in hereditary loading, erythrocytic accelerated Na-Li countertransport and lipid metabolism derangement.

Adolescent↗