Search results for "Prague"
showing 10 items of 652 documents
The superoxide anion is involved in the induction of long-term potentiation in the rat somatosensory cortex in vitro.
2004
Abstract The involvement of the superoxide anion (O2−) in the induction of neocortical long-term potentiation (LTP) was examined in rat brain slices containing the primary somatosensory cortex. Field potentials evoked by stimulation in cortical layer IV were recorded from layer II/III. In control experiments, tetanic high-frequency stimulation (HFS) resulted in essentially input-specific, NMDA receptor-dependent LTP (20.2±3.0% increase in field potential amplitude). When the availability of intracellular O2− was reduced by application of the cell membrane-permeable O2− scavengers MnTBAP or CP-H (spin trap), HFS-induced LTP was attenuated to 12.0±1.7% and 8.7±3.1% increase, respectively. In …
Role of the amygdala in antidepressant effects on hippocampal cell proliferation and survival and on depression-like behavior in the rat
2021
The stimulation of adult hippocampal neurogenesis by antidepressants has been associated with multiple molecular pathways, but the potential influence exerted by other brain areas has received much less attention. The basolateral complex of the amygdala (BLA), a region involved in anxiety and a site of action of antidepressants, has been implicated in both basal and stress-induced changes in neural plasticity in the dentate gyrus. We investigated here whether the BLA modulates the effects of the SSRI antidepressant fluoxetine on hippocampal cell proliferation and survival in relation to a behavioral index of depression-like behavior (forced swim test). We used a lesion approach targeting th…
Phosphorylation of extracellular signal-related protein kinase is required for rapid facilitation of heat-induced currents in rat dorsal root ganglio…
2005
A subgroup of dorsal root ganglion (DRG) neurons responds to noxious heat with an influx of cations carried by specific ion channels such as the transient receptor potential channel of the vanilloid receptor type, subtype 1 (TRPV1). Application of capsaicin induces a reversible facilitation of these currents. This facilitation could be an interaction of two agonists at their common receptor or be caused by an influx of calcium ions into the cell. Calcium influx into the cell can activate protein kinases such as the extracellular signal-related protein kinase (ERK) pathway. This study explored the kinetics, calcium-dependency and intracellular signals following application of capsaicin and l…
Dietary polyunsaturated fatty acids reduce retinal stress induced by an elevation of intraocular pressure in rats.
2011
International audience; N-6 and n-3 polyunsaturated fatty acids (PUFAs) have been shown to prevent tissue release of inflammatory molecules. We have shown that a combination of n-6 and n-3 PUFAs is more efficient than single supplementations on the long-term consequences of intraocular pressure elevation. We hypothesized that such an association is also more effective during early retinal stress by modifying retinal proinflammatory prostaglandin and cytokine productions. Rats were supplemented for 3 months with n-6 PUFAs, n-3 PUFAs, or both n-6 and n-3 PUFAs. After 3 months, a surgical elevation of intraocular pressure was induced. Retinal morphometry and glial cell activation were evaluate…
Long-term moderate magnesium-deficient diet shows relationships between blood pressure, inflammation and oxidant stress defense in aging rats
2006
International audience; Epidemiological and experimental studies have indicated a relationship among aging, dietary Mg, inflammatory stress, and cardiovascular disease. Our aim in the present study was to investigate possible links between dietary Mg, oxidant stress parameters, and inflammatory status with aging in rats. We designed a long-term study in which rats were fed for 22 months with moderately deficient (150 mg/kg), standard (800 mg/kg), or supplemented (3200 mg/kg) Mg diets. Comparisons were made with young rats fed with the same diets for 1 month. Compared to the standard and supplemented diets, the Mg-deficient diet significantly increased blood pressure, plasma interleukin-6, f…
Synthesis and pharmacological study of ethyl 1-methyl-5-(substituted 3,4-dihydro-4-oxoquinazolin-3-yl)-1H-pyrazole-4-acetates
2001
Several new ethyl 1-methyl-5-(substituted 3,4-dihydro-4-oxoquinazolin-3-yl)-1H-pyrazole-4-acetates 2, substituted at 2 and, alternatively at, 6, 7 or 8 positions of the quinazolinone nucleus, were synthesised. The compounds were screened for their analgesic and antiinflammatory activities, acute toxicity and ulcerogenic effect. Substitution in the benzene moiety of the quinazolinone ring did not show any advantage for the analgesic activity, whereas it improved in some cases the antiinflammatory activity. Some compounds showed appreciable antiinflammatory activity and, at the same time, very low ulcerogenic index.
1-imidazolyl(alkyl)-substituted di- and tetrahydroquinolines and analogues: syntheses and evaluation of dual inhibitors of thromboxane A(2) synthase …
2000
A series of 1-imidazolyl(alkyl)-substituted quinoline, isoquinoline, naphthalene, benzo[b]furan, and benzo[b]thiophene derivatives was synthesized as dual inhibitors of thromboxane A(2) synthase (P450 TxA(2)) and aromatase (P450 arom). Dual inhibition of these enzymes could be a novel strategy for the treatment of mammary tumors and the prophylaxis of metastases. The most potent dual inhibitors, 5-(2-imidazol-1-ylethyl)-7,8-dihydroquinoline (31) (P450 TxA(2): IC(50) = 0.29 microM; P450 arom: IC(50) = 0.50 microM) and its 5, 6-saturated analogue 30 (P450 TxA(2): IC(50) = 0.68 microM; P450 arom: IC(50) = 0.38 microM), showed a stronger inhibition of both target enzymes than the reference comp…
Adhesive interaction measured between AFM probe and lung epithelial type II cells
2007
The toxicity of inhaled nanoparticles entering the body through the lung is thought to be initially defined by the electrostatic and adhesive interaction of the particles with lung's wall. Here, we investigated the first step of the interaction of nanoparticles with lung epithelial cells using atomic force microscope (AFM) as a force apparatus. Nanoparticles were modeled by the apex of the AFM tip and the forces of interaction between the tip and the cell analyzed over time. The adhesive force and work of adhesion strongly increased for the first 100 s of contact and then leveled out. During this time, the tip was penetrating deeply into the cell. It first crossed a stiff region of the cell…
Acute cardio-respiratory effects in rats of PS4α, an antineoplastic peptidoglycan from Mycobacterium vaccae
2001
Abstract PS4α is a high molecular weight peptidoglycan extracted from Mycobacterium vaccae, which has demonstrated considerable antineoplastic activity in-vivo without apparent toxicity. Available for testing in only small quantities, a sensitive in-vivo method for measuring pulse and breathing rates in cannulated rats was applied to this compound at doses of 5, 50 and 500 μg kg−1. Various parameters (mean arterial pressure, maximum transpulmonary pressure, compliance, heart rate, minute volume, respiratory rate and tidal volume) were followed for up to 1 h and demonstrated no significant deviation in the baseline values obtained before injection. This compound at doses up to 500 μg kg−1 ha…
Small volume resuscitation with tempol is detrimental during uncontrolled hemorrhagic shock in rats.
2005
In a previous study, titration of a hypertonic saline (HTS) solution during severe uncontrolled hemorrhagic shock (UHS) failed to reduce mortality. In a separate study, a novel antioxidant, polynitroxylated albumin (PNA) plus tempol (4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl), infused during shock increased long-term survival. We hypothesized that combining potent antioxidants with a hypertonic solution during UHS would preserve the logistical advantage of small volume resuscitation and improve survival.An UHS outcome model in rats was used. UHS phase I (90 min) included blood withdrawal of 30 ml/kg over 15 min, followed by tail amputation for uncontrolled bleeding. At 20 min, rats wer…