[Recombinant human alpha-fetoprotein as a regulator of adipose tissue stromal cell activity].

Recombinant human alpha-fetoprotein (rhAFP) expressed in yeast system as a glycoprotein, was isolated and purified to 98% by multistep method. The testing of the rhAFP in the culture of adipose tissue stromal cells (hASC) has revealed its ability to enhance hASC proliferation and migration as well as vascular endothelial growth factor production, with no significant influence on cell invasion and matrix metalloproteinase-2 and -9 secretion. It has been also estimated that rhAFP is internalized in hASC via clathrin-dependent mechanism. A study in the murine experimental model of hindlimb ischemia has shown the capability of rhAFP to enhance blood flow recovery. These data suggest that rhAFP is a promising agent for enhancement of the hASC regenerative ability.

[Regulation of growth and remodeling of blood vessels: the unique role of urokinase].

Urokinase-plasminogen activator (uPA) is a multifunctional fibrinolytic protein activating growth factors, inducing proteolytic cascades, modulating cytokines, regulating receptor shedding, cellular phenotypic modulation and protein expression. These mechanisms underlie the ability of uPA to stimulate the key processes of vascular remodelling, atherosclerosis progression, restenosis and angiogenesis, -- cell migration and proliferation. We summarized data received by us and others concerning the role of uPA in blood vessel remodelling and growth. At the present stage, the uPA may be considered as a perspective target for influences directed on both the prevention of negative arterial remodelling and restenosis as well as the stimulation of vessel growth at ischemic diseases.

[Plasminogen activators and matrix metalloproteinases during arterial remodeling].

To evaluate the role and interaction of plasminogen activators and matrix metalloproteinases (MMPs) in arterial remodeling in vivo we compared effects of recombinant urokinase- (uPA) and tissue-type (tPA) plasminogen activators on vessel morphology, cell proliferation, inflammatory reaction and MMPs expression in arterial wall after experimental balloon angioplasty. We observed that the periadventitial application of uPA to the injured artery in pluronic gel stimulated neointima formation and inward arterial remodeling as well as cell proliferation and inflammatory leukocytes recruitment. In contrast, tPA attenuated neointima growth, contributed to outward arterial remodeling and did not affect significantly leukocytes recruitment in injured arterial wall. Perivascular uPA increased the content and activity of MMPs, while tPA did not induce such changes. In mouse model of vascular remodeling based on partial ligation of the carotid the content of uPA correlated with neointima growth, tPA content correlated with outward arterial remodeling. Our experiments suggest that plasminogen activators represent specific functional target for attenuating unfavorable inward arterial remodeling.

[Plasminogen activator of urokinase-type: mechanisms of involvement in vessel remodeling and angiogenesis, gene therapy approaches to ischemia]. / Urokinaznyi aktivator plazminogena: mekhanizmy uchastiia v remodelirovanii sosudov i angiogeneze, genno-terapevticheskie podkhody k revaskuliariztsii.

The review summarizes data obtained by the authors and other laboratories concerning the role of urokinase plasminogen activator in vessel remodeling and angiogenesis. The data have shown that urokinase is involved in unfavorable vascular remodeling during the development of restenosis, atherosclerosis and also in the regulation of angiogenesis. Urokinase is a promising target for therapeutic interventions aimed at restenosis prevention. Urokinase gene therapy may be a perspective strategy for the treatment of tissue ischemia.

[Effect of L-arginine on platelet aggregation, endothelial function adn exercise tolerance in patients with stable angina pectoris]. / Vliianie L-arginina na agregatsiiu trombotsitov, funktsiiu éndoteliia i tolerantnost' k fizicheskoi nagruzke u patsientov so stabil'noi stenokardiei napriazheniia.

AIM: Examination of the action of donor NO (L-arginine) on platelet aggregation, endothelial function and exercise tolerance in patients with stable angina of effort (SAE). MATERIAL AND METHODS: 42 patients with SAE (functional class I-II) and 10 healthy volunteers (control group) were assigned to two groups. 22 patients of group 1 were randomized to cross-over. They received cardiket (60 mg/day for 10 days or cardiket (60 mg/day) in combination with L-arginine (15 g/day for 10 days). 20 SAE patients of group 2 and control group received L-arginine (15 g/day for 10 days). In each group blood lipids were examined, and bicycle exercise test (BET) was performed. In addition, platelet aggregation and endothelial function were studied in group 2 and control group before and after the course of L-arginine. RESULTS: Compared to control group, endothelial function significantly improved in group 2 (from 5.0 +/- 2.9 to 7.8 +/- 4.1% vs 7.1 +/- 1.9 to 6.6 +/- 4.8%) (M +/- SD). BET duration increased in all the patients. After ADP addition in concentrations 1.5, 2.0, and 5.0 micromol/l platelet aggregation declined in 17 patients except 3 in whom the aggregation remained unchanged. CONCLUSION: Positive effect of L-arginine on endothelial function, exercise tolerance and platelet aggregation was observed in patients with stable angina of effort (functional class I-II). Therefore, arginine can be recommended as an adjuvant in the treatment of patients with ischemic heart disease.

[Disorders of hormone reception and intracellular signaling in hypertension]. / Narusheniia retseptsii gormonov i vnutrikletochnoi signalizatsii pri gipertonii.

This article discusses the disruption taking place due to hypertension in regulatory cell systems. These can either participate in development of the pathology or, on the opposite, provide compensation, be part of the mechanism that brings to normal the functional and metabolic state of cells under this disease. Data on increased level of Ca2+, higher reactivity of cells in relation of Ca2+ mobilizing hormones, alkalinisation of cytoplasma, activation of phosphoinozitide metabolism and stimulation of proteinkinaze C evidence in favour of the suggestion that these disruptions of regulatory cell systems are the material basis of the phenomenon of "structural support" to arterial hypertension.

[The status of the receptor-controlled calcium metabolism of the thrombocytes in patients in the early postoperative period]. / Sostoianie retseptorupravliaemogo kal'tsievogo obmena trombotsitov u bol'nykh v rannem posleoperatsionnom periode.

Basic changes in receptor-controlled platelet calcium metabolism that occur in the early postoperative period under the effect of aggregation-inducing hormones--platelet activation factor (PAF), adenosine phosphate (ADP) and vasopressin--are reviewed. Patients after lung surgery and patients with ischemic heart disease after aortocoronary bypass surgery have been examined. Patients operated on for malignant lung tumours developed increased postoperative sensitivity to ADP, while in patients after aortocoronary bypass surgery the early postoperative period was characterized by decreased sensitivity to PAF and vasopressin.

[Receptor-dependent regulation of the concentration of Ca2+ in the cytoplasm of thrombocytes in hypertensive patients]. / Retseptorzavisimaia reguliatsiia kontsentratsii Ca2+ v tsitoplazme trombotsitov bol'nykh gipertonicheskoi bolezn'iu.

Platelet activation factor (PAF)-, ADP and vasopressin-induced increments of platelet Ca2+ concentration were measured by quin-2 in 64 patients with essential hypertension and 16 normal donors. Basal concentration of free Ca2+ was 87 +/- 4 nM in donors, 106 +/- 5 nM in patients with labile hypertension (LH) and 122 +/- 6 nM in those with stable hypertension (SH) (p less than 0.01). PAF, ADP and vasopressin, added to platelets, increased [Ca]in by 448 +/- 58, 397 +/- 66, and 277 +/- 50 nM, respectively, in the donors, by 473 +/- 57, 479 +/- 54 and 195 +/- 32 nM, in LH patients, and by 607 +/- 85, 584 +/- 73 and 245 +/- 41 nM in SH patients. There were no significant variations between the three samples, using the ANOVA test. In 20 patients, whose both parents had essential hypertension, [Ca]in increment was 738 +/- 8 nM for PAF, 682 +/- 90 nM for ADP, and 320 +/- 61 nM for vasopressin. In 19 patients, who admitted to no essential hypertension in the family, these parameters were significantly lower: 310 +/- 40 nM for PAF, 389 +/- 61 nM for ADP, and 147 +/- 26 nM for vasopressin. The demonstrated changes may be making an important contribution to the maintenance of elevated vascular tone and provide an evidence in favor of a genetically-predetermined EH variety.

[Calcium metabolism of the thrombocytes in ischemic heart disease]. / Sostoianie kal'tsievogo obmena v trombotsitakh pri ishemicheskoi bolezni serdtsa.

Changes in Ca++ concentration were studied in platelets of patients with acute myocardial infarction, unstable or stable angina pectoris and those of healthy donors by means of fluorescent probe Quin-2 AM. Influence of aggregation inductors on the process of Ca++ level increase in these cells was also investigated. Intracellular Ca++ concentration increased in patients with acute myocardial infarction in the presence of PAF 2.10(-7) M (1337 +/- 255 nM) and in the presence of ADP 10(-5) M (1767 +/- 296 nM). A certain increase in calcium responses to stimulators was observed also in patients with unstable or stable angina pectoris. Dynamic follow up of patients with acute myocardial infarction starting from the 14th day demonstrated significant fall in intracellular Ca++ concentration (from 1767 +/- 296 nM to 834 +/- 186 nM, p less than 0.01). Platelet sensitivity to inductors during the course of therapy did not change significantly in patients with stable angina pectoris and tended to decrease in those with unstable angina pectoris (from 707 +/- 274 nM to 410 +/- 95 nM, p greater than 0.05). Increase in platelet aggregability and in calcium responses to stimulators in patients with IHD is an evidence of calcium metabolism disturbances which play an important role in the pathogenesis of the disease.

[Calcium metabolism in arterial hypertension. II. Changes in thrombocyte sensitivity to verapamil]. / Obmen kal'tsiia pri arterial'noi gipertonii. Soobshchenie II. Izmeneniia chuvstvitel'nosti trombotsitov k verapamilu.

Verapamil produced dose-dependent inhibition of ADP- and TAF-induced increase in thrombocyte calcium concentration in hypertensive patients. Sensitivity to verapamil tested by EC50-half-maximal inhibition of responses to hormones can be weakened in vitro by adrenalin and strengthened by papaverin. Thrombocytes of hypertensive patients were individually sensitive to combination of papaverin and verapamil. The cellular sensitivity to verapamil disappeared when clonidine was substituted for verapamil and was restored when papaverin was added to verapamil.

[Calcium metabolism in arterial hypertension. I. Myocardial hypertrophy and hormone-dependent increase in Ca2+ levels in the thrombocytes of patients with arterial hypertension]. / Obmen kal'tsiia pri arterial'noi gipertonii. Soobshchenie I. Gipertrofiia miokarda i gormonzavisimoe uvelichenie kontsentratsii Ca2+ v trombotsitakh bol'nykh arterial'noi gipertoniei.

Clonidine-treated patients with essential hypertension demonstrated reliable positive correlations between echocardiographically determined signs of myocardial hypertrophy (thickness of left ventricular posterior wall and interventricular septum, left ventricular myocardial mass) and hormone-dependent increase in thrombocyte calcium concentration induced by ADP and TAF. Antihypertensive therapy was more effective in patients with relatively weak cellular effect of Ca-increasing hormone response having no signs of myocardial hypertrophy.

[Effect of hypotensive therapy on a receptor-dependent increase in Ca2+ in the thrombocytes of patients with hypertension]. / Vliianie gipotenzivnoi terapii na retseptorzavisimoe povyshenie soderzhaniia Ca2+ v trombotsitakh bol'nykh gipertonicheskoi bolezn'iu.

The effect of antihypertensive drugs on receptor-dependent increase in Ca2+ basal level and its changes under stimulators action (thrombocytes activating factor, ADP and vasopressin) were studied by means of a fluorescent calcium probe "quin-2". Nifedipine blocked receptor-dependent increase of Ca2+ in thrombocytes in vitro as well as by oral administration, which was accompanied by decrease in vascular tone and BP. The degree of BP decrease correlated with that of depression of receptor-dependent increase of Ca2+ in thrombocytes. Combined therapy including nifedipine, propranolol and a diuretic resulted in more manifest inhibition of receptor-dependent calcium channels than monotherapy with nifedipine. Effect of antihypertensive drugs evidently depends on their influence on receptor-dependent Ca2+ cellular entrance.

[New approaches to the study of the mechanism of action of nitrates]. / Novye podkhody k izucheniiu mekhanizma deistviia nitratov.

The effects of nitrates on a Ca+2 increase and the content of cyclic nucleotides in human platelets were studied. Nitroglycerin (GTN), isosorbide dinitrate (ISDN) and sodium nitroprusside (NP) were found to inhibit dose-dependently the intracellular Ca+2 increase induced by the platelet activating factor (PAF). The inhibiting effect of NP was at lower concentrations than those of GTN and ISDN. GTN calcium blocking action did not change significantly regardless of vasopressin, serotonin or PAF used as inducers of the intracellular Ca+2 increase. GTN suppressed the PAF provoked Mn+2 entering into the cells. NP and GTN induced increase of the cGMP content correlated with their calcium blocking activity. They did not augment the level of cAMP. Methylene blue (MB), a guanylate cyclase and glutathione reductase inhibitor, decreased the calcium blocking effect of GTN and its influence on the cGMP content but failed to suppress the inhibitory effect of NP. Ascorbic acid increased the calcium blocking effect of NP but did not influence the inhibitory effect of GTN. An increase in Ca+2 content induced by PAF in platelets from patients with chronic congestive heart failure was significantly higher in the group with dilatation cardiomyopathy. The effect of 10 mg of ISDN sublingually on forearm venous tone was higher in patients with initially elevated venous tone. There was a direct statistical correlation between the IC50 of GTN calcium blocking effects in platelets and the elevation of a forearm venous tone reaction from a statistic mean reaction to ISDN.(ABSTRACT TRUNCATED AT 250 WORDS)

[Calcium-blocking effect of nitro compounds in human platelets: correlation with changes in the cyclic guanosine monophosphate level]. / Kal'tsiiblokiruiushchee deistvie nitrosoedinenii na trombotsity cheloveka: korreliatsiia s izmeneniem soderzhaniia tsiklicheskogo guanozinmonofosfata.

The effects of nitrates on Ca2+ increase and cyclic nucleotide content in human platelets were studied. Nitroglycerin, isosorbide dinitrate and sodium nitroprusside were found to inhibit the intracellular Ca2+ increase induced by the platelet activating factor, ADP and a stable thromboxane A2 analog--U46619. The inhibiting effect of sodium nitroprusside manifested itself at lower concentrations than those of nitroglycerin and isosorbide dinitrate. Nitroglycerin suppressed the Mn2+ entry into the cells and caused a 2-fold increase of the cGMP content which correlates with the calcium blocking activity. Methylene blue, a guanylate cyclase and glutathione reductase inhibitor, decreased the calcium blocking effect of nitroglycerin and its influence on the cyclic nucleotide content but failed to suppress the inhibitory effect of sodium nitroprusside. The data obtained suggest that the effects of nitrates on platelets are mediated by their influence on guanylate cyclase which leads to a cyclic nucleotide content increase and to a calcium blocking effect.

[The use of pharmacological preparations for the study of calmodulin interaction with enzymes]. / Ispol'zovanie farmakologicheskikh soedinenii dlia izucheniia vzaimodeistviia kal'modulina s fermentami.

Calmodulin-dependent regulation of cyclic nucleotide phosphodiesterase and kinase phosphorylase activities as well as Ca2+-dependent regulation of kinase phosphorylase, mediated via the integrated calmodulin, were studied in presence of phenothiazine and butyrophenone series of pharmacological drugs. As compared with butyrophenones, phenothiazines were shown to be more effective inhibitors of calmodulin-dependent activation of the phosphodiesterase. Phenothiazines inhibited similarly the effect of calmodulin on activity of kinase phosphorylase, whereas they did not affect the Ca2+-dependent activity of kinase phosphorylase. At the same time, butyrophenones proved to inhibit the Ca2+-dependent activation of kinase phosphorylase, mediated via integrated calmodulin as well as these drugs inhibited uniformly the calmodulin-dependent regulation of both kinase phosphorylase and phosphodiesterase. The data obtained suggest that dissimilar effect of phenothiazines on calmodulin-dependent regulation of kinase phosphorylase and phosphodiesterase, carried out using dissimilar mechanisms, required an extreme caution in evaluation of physiological and biochemical experiments, where these drugs were used as means for study of calmodulin functions in biological processes.

[Induction of Ca2+ ion transport in human thrombocytes as affected by thyroid hormone receptors from malignant transformed cells]. / Induktsiia transporta ionov Ca2+ v trombotsitakh cheloveka pod deistvie retseptora tireoidnykh gormonov zlokachestvenno transformirovannykh kletok.

The effect of thyroid hormone receptors isolated from normal and malignant cells on the induction of Ca2+ transport to platelets was studied. It is established that the receptor isolated from malignant cells by thyroxin (T4) or triiodothyronine (T3) stimulates (three-fold) the induction of Ca2+ transport to platelets. The effect is blocked by verapamil, which is the inhibitor of Ca2+ channels in plasma membranes. It is shown that neither the receptor of cancer cells, nor hormones (T3 or T4) influence the transport of Ca2+ to platelets without preliminary complexing. The hormone-receptor complex failed to affect the concentration of "cytoplasmic" Ca2+ in platelets analogous experimental conditions. It is suggested that the increased Ca2+ content in cancer cells can be partially attributed to the ability of thyroid hormone receptor of cancer cells to induce Ca2+ transport across the plasma membrane.