Search results for "Wistar"
showing 10 items of 1094 documents
A preclinical study to model taurine pharmokinetics in the undernourished rat
2018
AbstractMalnutrition is a common feature of chronic and acute diseases, often associated with a poor prognosis, including worsening of clinical outcome, owing, among other factors, to dysfunction of the most internal organs and systems affecting the absorption, metabolism and elimination of drugs and nutrients. Taurine is involved in numerous biological processes and is required in increased amounts in response to pathological conditions. The aim of this study was to describe the behaviour of taurine in well-nourished (WN) rats and to analyse the influence of protein–energy undernutrition on the pharmacokinetic (PK) parameters of taurine, using a PK model. Wistar rats were randomly distribu…
Neuronal nitric oxide synthase is involved in CB/TRPV1 signalling: Focus on control of hippocampal hyperexcitability
2017
Cannabinoids (CB), transient receptors potential vanilloid type 1 (TRPV1) and nitric oxide (NO) were found to be interlinked in regulating some neuronal functions such as membrane excitability and synaptic transmission. TRPV1 play a fundamental role since it represents a synaptic target for CB that triggers several downstream cellular pathways. In this regard, recent evidence report that TRPV1 could influence NO production by modulating neuronal NO synthase (nNOS) activity. In the present research, we pointed to manipulate nNOS function to assess its role on TRPV1 signalling in hyperexcitability conditions elicited in the dentate gyrus of hippocampal formation. The activation of TRPV1 recep…
In vitro assessment of competitive and time-dependent inhibition of the nevirapine metabolism by nortriptyline in rats
2018
Abstract Nevirapine (NVP) is a non-nucleoside reverse transcriptase inhibitor of human immunodeficiency virus type 1 (HIV-1) widely used as a component of High Active Antiretroviral Therapy (HAART) since it is inexpensive, readily absorbed after oral administration and non-teratogenic. In the present work, the mechanism of a previously described pharmacokinetic interaction between NVP and the antidepressant drug nortriptyline (NT) was studied using rat hepatic microsomes. The obtained results showed a competitive inhibition of the NVP metabolism by NT. The three main NVP metabolites (2-OH-NVP, 3-OH-NVP and 12-OH-NVP) where competitively inhibited with similar inhibitory constant values (Ki …
Pancreatic Protein Tyrosine Phosphatase 1B Deficiency Exacerbates Acute Pancreatitis in Mice
2016
Acute pancreatitis (AP) is a common and devastating gastrointestinal disorder that causes significant morbidity. The disease starts as local inflammation in the pancreas that may progress to systemic inflammation and complications. Protein tyrosine phosphatase 1B (PTP1B) is implicated in inflammatory signaling, but its significance in AP remains unclear. To investigate whether PTP1B may have a role in AP, we used pancreas PTP1B knockout (panc-PTP1B KO) mice and determined the effects of pancreatic PTP1B deficiency on cerulein- and arginine-induced acute pancreatitis. We report that PTP1B protein expression was increased in the early phase of AP in mice and rats. In addition, histological an…
Non-uniform displacement and strain between the soleus and gastrocnemius subtendons of rat Achilles tendon
2018
Achilles tendon (AT) comprises of 3 subtendons arising from the soleus (SOL) and the lateral (LG) and medial (MG) heads of the gastrocnemius muscle. While recent human studies show differential displacement within AT, these displacements have not been attributed to specific subtendons. We tested the hypothesis that the SOL and LG subtendons show differential displacement and strain during various combinations of SOL, LG, and MG excitations. Movement of knots, sutured onto SOL and LG subtendons of 12 Wistar rats, was videotaped, while the muscles were stimulated intramuscularly and ankle torque was assessed. When SOL only was stimulated, the plantar flexion torque was the smallest among the …
Brain BDNF levels are dependent on cerebrovascular endothelium-derived nitric oxide
2016
International audience; Scientific evidence continues to demonstrate a link between endothelial function and cognition. Besides, several studies have identified a complex interplay between nitric oxide (NO) and brain-derived neurotrophic factor (BDNF), a neurotrophin largely involved in cognition. Therefore, this study investigated the link between cerebral endothelium-derived NO and BDNF signaling. For this purpose, levels of BDNF and the phosphorylated form of endothelial NO synthase at serine 1177 (p-eNOS) were simultaneously measured in the cortex and hippocampus of rats subjected to either bilateral common carotid occlusion (n=6), physical exercise (n=6) or a combination of both (n=6) …
Chronic Administration of Quercetin Induces Biomechanical and Pharmacological Remodeling in the Rat Coronary Arteries
2017
Acute dilation brought about by the dietary flavonoid quercetin in coronary arterioles has been described earlier, but no information is available on its chronic effects. Male Wistar rats (body weight about 190 g) were divided to two groups: the quercetin-treated group (n=22) had quercetin supplementation of approximately 30 mg/kg/day, whereas the control group (n=20) had none. After eight weeks of treatment, intramural coronary arterioles with identical passive diameters (178+/-14 microm and 171+/-9 microm) were prepared and their biomechanics and pharmacological reactivities were tested using pressure arteriography ex vivo. The spontaneous tone of quercetin-treated arteries was higher (16…
Methodological Approach to Use Fresh and Cryopreserved Vessels as Tools to Analyze Pharmacological Modulation of the Angiogenic Growth
2016
The sprouting of new vessels is greatly influenced by the procedure chosen. We sought to optimize the experimental conditions of the angiogenic growth of fresh and cryopreserved vessels cultured in Matrigel with the aim to use this system to analyze the pharmacological modulation of the process. Segments of second-order branches of rat mesenteric resistance arteries, thoracic aorta of rat or mouse, and cryopreserved rat aorta and human femoral arteries were cultured in Matrigel for 7-21 days in different mediums, as well as in the absence of endothelial or adventitia layer. Quantification of the angiogenic growth was performed by either direct measurement of the mean length of the neovessel…
Lamotrigine differently modulates 7-Nitroindazole and L-Arginine influence on Rat Maximal Dentate Gyrus Activation
2007
The effects induced on the maximal dentate gyrus activation (MDA) by administering the anticonvulsant lamotrigine (LTG), the selective inhibitor of neuronal nitric oxide synthase 7-nitroindazole (7-NI) and the precursor of nitric oxide (NO) synthesis L-arginine, alone or in combination, were studied in urethane anaesthetized rats. Either 7-NI or LTG alone administration reduced the number of convulsing animals following angular bundle (AB) stimulation; their combined treatment induced a further increase of the anticonvulsant effect as also demonstrated by the decrease of MDA and afterdischarge (AD) durations in the animals still responding to AB stimulation. On the contrary, the injection o…
In the rat maximal dentate activation model of partial complex epilepsy, the anticonvulsant activity of levetiracetam is modulated by nitric oxide-ac…
2009
The effects of nitric oxide-active drugs on the anticonvulsant action of the antiepileptic drug levetiracetam in an experimental model of partial complex seizures named maximal dentate gyrus activation were studied in rats. Levetiracetam was given alone or in combination with 7-nitroindazole, a preferential inhibitor of neuronal nitric oxide synthase, or with L: -arginine, the precursor of nitric oxide synthesis. The maximal dentate activation parameters were the time of latency and the durations of maximal dentate activation and afterdischarge responses. The administration of levetiracetam showed an anticonvulsant effect that was increased when given in combination with 7-nitroindazole. Th…