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Matrai M.,Institute of Human Physiology and Clinical Experimental Research | Hetthessy J.R.,Semmelweis University | Mericli M.,Semmelweis University | Acs N.,Semmelweis University | And 2 more authors.

Objective:Hypertension causes adverse remodeling and vasomotor alterations in coronaries. Hormones such as estrogen may help counterbalance some of these effects. The aim of this study was to analyze the effects of ovariectomy and estrogen therapy in a rat model of menopausal hypertension induced by angiotensin II (AII). Methods:We investigated diameter, tone, and mechanics of intramural coronaries taken from ovariectomized female rats (n=11) that received chronic AII treatment to induce hypertension, and compared the results with those found in female rats that were also given estrogen therapy (n=11). The "hypertensive control" group (n=11) underwent an abdominal sham operation, and received AII. After 4 weeks of AII treatment, side branches of left anterior descendent coronary (approximately 200μm in diameter) were isolated, cannulated with plastic microcannulas at both ends, and studied in vitro in a vessel chamber. The inner and outer diameter of the arteries were measured by microangiometry, and spontenuous tone, wall thickness, wall cross-sectional area, tangential stress, incremental distensibility, circumferential incremental elastic modulus, thromboxane agonist-induced tone, and bradykinin-induced dilation were calculated. Results:In hypertension, intramural small coronaries show inward eutrophic remodeling after ovariectomy comparing with hypertensive controls. Estrogen therapy had an opposite effect on vessel diameter. Hormone therapy led to an increase in spontaneous tone, allowing for greater dilatative capacity. Conclusions:Estrogen may therefore be considered to counterbalance some of the adverse changes seen in the wall of intramural coronaries in the early stages of chronic hypertension. © 2016 by The North American Menopause Society. Source

Vastagh I.,Semmelweis University | Horvath T.,Institute of Human Physiology and Clinical Experimental Research | Garamvolgyi Z.,Semmelweis University | Rosta K.,Semmelweis University | And 5 more authors.
Acta Physiologica Hungarica

Women with gestational diabetes mellitus (GDM) are at high risk of subsequently developing type 2 diabetes mellitus which is an important cardiovascular risk factor. We have evaluated whether preclinical morphological and functional arterial changes are present in GDM. Diameter, intima-media thickness (IMT), intima-media cross-section area (IMCSA) and elasticity features (compliance, distensibility coefficient, circumferential strain, stiffness index (SI) α and β, incremental elastic modulus) of the common carotid arteries (CCA) were studied in the 3rd trimester in 25 women with GDM, and 17 normal pregnant women matched for age and body mass index using an ultrasonographic vessel wall-movement tracking system and applanation tonometry. Mean IMT, IMCSA and SI α tended to be larger, whereas compliance was smaller in women with GDM but none of these differences were significant. Serum glucose (4.99±0.51 vs. 4.79±0.61 mmol/L, p=0.37) and HbA1c (5.33±0.27 vs. 5.36±0.47 mmol/L, p=0.85) proved normoglycemia in both groups. In conclusion, by the combination of methods we applied in this case control study, neither morphological nor functional characteristics of large elastic arteries differ significantly between well-treated normoglycemic women with GDM and non-diabetic pregnant women in the 3rd trimester. © 2011 Akadémiai Kiadó, Budapest. Source

Horvathy D.B.,Semmelweis UniversityBudapest Hungary | Vacz G.,Institute of Human Physiology and Clinical Experimental Research | Szabo T.,Hungarian Academy of Sciences | Szigyarto I.C.,Hungarian Academy of Sciences | And 4 more authors.
Journal of Biomedical Materials Research - Part B Applied Biomaterials

Blood serum fractions are hotly debated adjuvants in bone replacement therapies. In the present experiment, we coated demineralized bone matrices (DBM) with serum albumin and investigated stem cell attachment in vitro and bone formation in a rat calvaria defect model. In the in vitro experiments, we observed that significantly more cells adhere to the serum albumin coated DBMs at every time point. In vivo bone formation with albumin coated and uncoated DBM was monitored biweekly by computed tomography until 11 weeks postoperatively while empty defects served as controls. By the seventh week, the bone defect in the albumin group was almost completely closed (remaining defect 3.0±2.3%), while uncoated DBM and unfilled control groups still had significant defects (uncoated: 40.2±9.1%, control: 52.4±8.9%). Higher density values were also observed in the albumin coated DBM group. In addition, the serum albumin enhanced group showed significantly higher volume of newly formed bone in the microCT analysis and produced significantly higher breaking force and stiffness compared to the uncoated grafts (peak breaking force: uncoated: 15.7±4 N, albumin 46.1±11 N). In conclusion, this investigation shows that implanting serum albumin coated DBM significantly reduces healing period in nonhealing defects and results in mechanically stronger bone. These results also support the idea that serum albumin coating provides a convenient milieu for stem cell function, and a much improved bone grafting success can be achieved without the use of exogenous stem cells. © 2015 Wiley Periodicals, Inc. Source

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