Search results for "Tissue Culture Technique"

Novel antihypertensive hexa- and heptapeptides with ACE-inhibiting properties: From the in vitro ACE assay to the spontaneously hypertensive rat

2011

Bioactive ACE inhibiting peptides are gaining interest in hypertension treatment. We have designed and screened six synthetic heptapeptides (PACEI48 to PACEI53) based on two hexapeptide leads (PACEI32 and PACEI34) to improve ACE inhibitory properties and assess their antihypertensive effects. ACE activity was assayed in vitro and ex vivo. Selected peptides were administered to spontaneously hypertensive rats (SHRs) and normotensive Wistar-Kyoto (WKY) rats. In vitro cytotoxicity was assessed with the MTT reduction test. The six heptapeptides at low micromolar concentration produced different degrees of in vitro inhibition of ACE activity using the synthetic substrate HHL or the natural subst…

Oxidative Inhibition of the Mitochondrial Aldehyde Dehydrogenase Promotes Nitroglycerin Tolerance in Human Blood Vessels

2007

Objectives We tested the hypothesis of whether an inhibition of the nitroglycerin (GTN) bioactivating enzyme mitochondrial aldehyde dehydrogenase (ALDH-2) contributes to GTN tolerance in human blood vessels. Background The hemodynamic effects of GTN are rapidly blunted by the development of tolerance, a phenomenon associated with increased formation of reactive oxygen species (ROS). Recent studies suggest that ROS-induced inhibition of ALDH-2 accounts for tolerance in animal models. Methods Segments of surgically removed arteria mammaria and vena saphena from patients undergoing coronary bypass surgery were used to examine the vascular responsiveness to GTN and the endothelium-dependent vas…

Metabolism of reduced pyridine nucleotides in ascites cell nuclei

1964

1. The conditions are described under which the fluorescence due to reduced pyridine nucleotides can be studied separately at nuclear and cytoplasmic sites of glass-grown ascites cells, by the use of a flow chamber in the microfluorimeter ofChance andLegallais.

A subset of ventral tegmental area dopamine neurons responds to acute ethanol

2015

The mechanisms by which alcohol drinking promotes addiction in humans and self-administration in rodents remain obscure, but it is well known that alcohol can enhance dopamine (DA) neurotransmission from neurons of the ventral tegmental area (VTA) and increase DA levels within the nucleus accumbens and prefrontal cortex. We recorded from identified DA neuronal cell bodies within ventral midbrain slices prepared from a transgenic mouse line (TH-GFP) using long-term stable extracellular recordings in a variety of locations and carefully mapped the responses to applied ethanol (EtOH). We identified a subset of DA neurons in the medial VTA located within the rostral linear and interfascicular n…

Animal Models of Cardiovascular Disease

2009

The use of animal models to study cardiovascular disease has made a substantial contribution to increasing our understanding of disease pathogenesis, has led to the development of diagnostic techniques, and has made it possible to verify the effectiveness of different preventative and therapeutic approaches, whether pharmacological or interventional. The main limitations stem from differences between human and experimentally induced pathology, in terms of both genetic regulatory mechanisms and factors that influence cardiovascular function. The experimental models and preparations used in cardiovascular research include those based on isolated cells or tissues or structures immersed in orga…

Evidence for a negative inotropic effect of obesity in human myocardium?

2009

Objective: The present study was performed as an attempt to analyze the relationship between body weight and human myocardial performance. As overweight is frequently associated with hypertension, stenosis of epimyocardial coronary arteries and other factors that influence myocardial performance, the experimental model of isolated human atrial myocardium was selected. Atrial contractile performance does neither depend on the extent of stenosis of epicardial coronary arteries nor on the degree of hypertension and its secondary pathology. Methods:Rightatrialmusclepreparations(0.5 6 mm)of183patientsundergoingcoronaryarterybypasssurgerywereelectricallystimulatedat optimal length. Active tension…

Cell culture models of higher complexity in tissue engineering and regenerative medicine.

2007

Cell culture techniques have tended to be used in biomaterial research as a screening method prior to embarking on specific in vivo experimentation. This presentation aims at showing that it is possible to develop more sophisticated in vitro systems using primary human cells in co-culture with other cell types and biomaterials in a three-dimensional setting. While the predictive value of such systems is still not proven these models can be employed to unravel the complexity of biological systems in order to understand molecular mechanisms of cell-cell and cell-material interactions. The brief overview is under the headings of basic principles of relevant culture systems, the study of inflam…

Searching for wheat plants with low toxicity in celiac disease: Between direct toxicity and immunologic activation.

2009

Abstract Background Natural or induced variations in the noxiousness of gluten proteins for celiac disease (CD) patients are currently being investigated for their potential in breeding wheat crops with reduced toxicity. Aims We evaluated the bread wheat line C173 for its effects on the in vitro -grown duodenal mucosa of CD patients. Methods In vitro -grown duodenal mucosa biopsies of 19 CD patients on a gluten-free diet were exposed to peptic/tryptic-digested prolamins from bread wheat line C173 lacking gliadin–glutenin subunits, analyzed for morphology, cytokine and anti-tTG antibody production, and compared with mucosa biopsies exposed to prolamins from wild-type cv. San Pastore. Results…

Neuroprotective properties of xenon and helium in an in vitro model of traumatic brain injury: one small step or one big jump?

2008

Factors influencing axillary shoot proliferation and adventitious budding in cedar.

2005

We developed procedures for in vitro cloning of Cedrus atlantica Manetti and C. libani A. Rich explants from juvenile and mature plants. Explant size was one determinant of the frequency of axillary bud break in both species. Shoot tips and nodal explants mainly developed calli, whereas bud sprouting occurred in defoliated microcuttings cultured on a modified Murashige and Skoog medium without growth regulators. Isolation and continuous subculture of sprouted buds on the same medium allowed cloning of microcuttings from C. atlantica and C. libani seedlings and bicentennial C. libani trees, thus providing a desirable alternative for multiplying mature trees that have demonstrated superior ch…