Search results for "Agoni"
showing 10 items of 2493 documents
Antihistaminic and anticholinergic activities of mequitazine in comparison with clemizole
1988
Abstract The antihistamine and anticholinergic properties of mequitazine have been investigated and compared with those of clemizole. Both mequitazine and clemizole antagonized the effect of histamine in guinea-pig ileum competitively, the pA2 values calculated by Schild plot were 9.95 ± 0.44 for mequitazine and 10.54 ± 0.44 for clemizole. Mequitazine at 10−7 M produced a parallel shift of the dose-response curve to acetylcholine in the rat duodenum, clemizole and the lower doses of mequitazine failed to modify the effect of acetylcholine. The potency of mequitazine and clemizole as H1-histamine blockers is similar, but only mequitazine at highest concentration used showed anticholinergic a…
Chronic oral haloperidol and clozapine in rats: A behavioral evaluation.
1999
The present study evaluated chronic oral treatment of rats with haloperidol or clozapine. Drugs were given in the drinking water for a 23-day period . Rat behavior was analyzed once a week in an open field. Rats ingested either 1.7 mg/kg haloperidol or 40 mg/kg clozapine daily. Blood serum analysis revealed concentrations of 6 ng/ml for haloperidol and 22 ng/ml for clozapine at the end of the treatment. Haloperidol decreased overall activity from the onset of treatment. Clozapine showed similar effects only on the last test day. Control animals showed a slight habituation in exploration-related parameters. In conclusion, these results indicate that oral drug administration through the drink…
Effects of Different Opioid Receptor Antagonists on the Electrically-Evoked Release of Endogenous Dopamine from the Isolated Neural Lobe of the Rat P…
2009
Abstract Isolated neural lobes of the rat pituitary gland were incubated in Krebs-HEPES solution which contained the dopamine uptake inhibitor GBR 12921 and in some experiments additionally pargyline. The release of endogenous dopamine evoked by electrical stimulation of the pituitary stalk was determined by high-performance liquid chromatography with electrochemical detection. (+/-)- Naloxone increased the evoked dopamine release maximally by 440% (EC(50) 209 nM). The (+)-enantiomer of naloxone (up to 10 muM) did not affect the release of dopamine. The preferential kappa-opioid receptor antagonist MR 2266 increased the evoked dopamine release maximally by 135% (EC(50) 7 nM). MR 2267, the i…
Ghrelin reduces hepatic mitochondrial fatty acid beta oxidation.
2007
Ghrelin is a 28-amino-acid peptide secreted during starvation by gastric cells. Ghrelin physiologically induces food intake and seems to alter lipid and glucid metabolism in several tissues such as adipose tissue and liver. Liver has a key position in lipid metabolism as it allows the metabolic orientation of fatty acids between oxidation and esterification. We investigated the effects of peripheral ghrelin administration on 2 crucial parameters of fatty acid oxidation: the levocarnitine (L-carnitine)-dependent entry of the fatty acids in the mitochondria and the mitochondrial fatty acid oxidation. Ghrelin was either given to rats prior to the hepatocyte preparation and culture or used to t…
3H-cyproterone acetate: binding characteristics to human uterine progestagen receptors
1985
The availability of tritium labeled cyproterone acetate (CPA) facilitated the systematic investigation of the binding characteristics of this compound for human uterine progesterone receptors (PgR). The binding parameters of 3H-CPA are compared to those of 3H-R5020 and 3H-progesterone. The rate constants of association (k1M-1sec-1) to PgR were 7.8 X 10(3) for 3H-R5020, 4.5 X 10(4) for 3H-progesterone and 4.0 X 10(4) for 3H-CPA. The rate constants of dissociation (k-1, sec-1) were 3.6 X 10(-5) for 3H-R5020, 21.3 X 10(-5) for 3H-progesterone and 17.8 X 10(-5) for 3H-CPA. The Kd-values (M), as obtained by titration analysis and subsequent Scatchard plot analysis were 1.2 X 10(-9) for 3H-R5020,…
Raloxifene promotes prostacyclin release in human endothelial cells through a mechanism that involves cyclooxygenase-1 and -2
2005
Objective To examine the effects of raloxifene on prostacyclin production by human umbilical vein endothelial cells (HUVEC) and to shed light on the molecular details of that action. Design Cell culture for 4, 8, 16, 24, and 48 hours. Setting University research laboratory. Patient(s) Source of HUVEC. Intervention(s) Measurement of prostacyclin production and of protein levels and mRNA expression of cyclooxygenase (COX)-1 and -2. Main Outcome Measure(s) Prostacyclin production was measured by enzyme immunoassay, the mRNA expression of COX-1 was measured by quantitative real time-polymerase chain reaction, and the protein levels of COX-1 and -2 were measured by immunoblotting. Result(s) Ralo…
Characteristics of histamine tachyphylaxis in rat uterine smooth muscle.
2002
Objective and design: To study both the desensitisation induced by short-term exposure to histamine and the mechanism responsible in the isolated rat uterus.¶Material: Precontracted isolated uterus (37 mM KCl) from oestrogenised Wistar rats were used.¶Treatment: Repetitive responses to histamine (10–6, 10–5, 10–4, 10–3 M), dimaprit and clonidine (10–4 M) were tested at 15, 30, 45 and 105 min., with their modifications by (5 mg/ kg, 24 h before sacrifice) reserpine, 10–7 M propranolol, 10–8 M atropine, and 10–6 M indomethacin. Dose-response curves for adrenaline were carried out as standard protocol.¶Methods: In vitro techniques (de Jalon's solution, 31°C, carbogen, isotonic registration, re…
Oestrogen receptor subtype-specific repression of calpain expression and calpain enzymatic activity in neuronal cells - implications for neuroprotect…
2006
Calpains represent a superfamily of Ca2+-activated cysteine-proteases, which are important mediators of apoptosis and necrosis. In the brain, m-calpain and micro-calpain, the two ubiquitous calpain-isoforms, are strongly activated in neurones after an excitotoxic Ca2+ influx occurring, for example, during cerebral ischemia. Because oestrogen and its receptors (ERalpha/ERbeta) can exert neuroprotective activity, we investigated their influence on expression of calpains and their endogenous inhibitor, calpastatin. We found that ectopic expression of ERalpha in human neuroblastoma SK-N-MC cells led to a ligand-independent constitutive down-regulation of m-calpain accompanied by an up-regulatio…
Postnatal weight change is influenced by mother-newborn pair leptin levels
2000
We investigated serum leptin levels in 103 mother-newborn-pairs; Cord leptin was significantly higher than mother's leptin (5.7 ± 5.5 vs. 22.1 ± 19.9 ng/ml; p <0.001). Cord leptin was significantly higher in females than males (6.9 ± 6.3 vs. 3.9 ± 3.6 ng/ml respectively; p <0.001), and correlated with maternal leptin (r = 0.24; p = 0.001), gestational age (r = 0.54; p <0.001), and birth weight (r = 0.56; p <0.001). Neonatal leptin at the 4(th) day significantly correlated with percent weight loss in the first four days of life. These observations shed light on the origin of cord leptin and on the role of leptin in postnatal weight loss. (C) 2000 Elsevier Science Inc.
Management of Diabetes in Candidates for Liver Transplantation and in Transplant Recipients.
2021
Diabetes is common in patients wait-listed for liver transplantation due to end-stage liver disease or to hepatocellular cancer as well as in post-transplant phase (post-transplantation diabetes mellitus-PTDM). In both conditions the presence of diabetes severely affects disease burden and long-term clinical outcomes; careful monitoring and appropriate treatment are pivotal to reduce cardiovascular events and graft and recipients' death. We thoroughly reviewed the epidemiology of diabetes in the transplant setting and the different therapeutic options, from lifestyle intervention to antidiabetic drug use - including the most recent drug classes available - and to the inclusion of bariatric …