Search results for "Pentobarbital"
showing 10 items of 14 documents
Taurine potentiates the anticonvulsive effect of the GABAAagonist muscimol and pentobarbital in the immature mouse hippocampus
2019
Objective The high incidence of epileptic seizures in neonates and their frequent refractoriness to pharmacologic therapies require identification of new therapeutical options. Therefore, we investigated whether the modulatory effect of taurine on γ-aminobutyric acid (GABA)A receptors can enhance the anticonvulsive potential of the GABAA receptor agonist muscimol and of the barbiturate pentobarbital. Methods We performed field potential recordings in in toto hippocampus preparations of immature (postnatal days 4-7) C57Bl/6 mouse pups. Spontaneous epileptiform activity was induced by the continuous presence of the potassium channel blocker 4-aminopyridine and the glycinergic antagonist stryc…
Determination of barbiturates in urine by micellar liquid chromatography and direct injection of sample.
2000
Abstract A liquid chromatographic procedure for the determination of six barbiturates (barbital, diallyl barbituric acid, phenobarbital, butabarbital, amobarbital and pentobarbital) in urine samples is described. The proposed system uses a Spherisorb octadecyl-silane ODS-2 C 18 analytical column and a guard column of similar characteristics. The UV detector was set at 240 nm. A study to select adequate composition of the micellar mobile phase for the separation of these compounds in urine samples is performed. Maximum resolution was achieved with a 0.07 M sodium dodecylsulphate-0.3% propanol at pH 7.4 eluent. Limits of detection at 240 nm were ranged between 0.13 μg ml −1 for diallyl barbit…
DETERMINATION OF PENTOBARBITAL IN BIOLOGICAL SAMPLES BY MICELLAR LIQUID CHROMATOGRAPHY
1999
A liquid chromatographic procedure for the determination of pentobarbital in urine and plasma samples is described. The proposed system uses a Spherisorb octadecyl-silane ODS-2 C18 analytical column, a guard column of similar characteristics, and a 0.02 M CTAB-15% 1-propanol at pH 7.5 mobile phase. The UV detector was set at 250 nm. Pentobarbital was isolated from urine and plasma samples by using a single solid phase extraction procedure with LMS cartridges. Mephobarbital was used as internal standard. Limits of detection were 0.53 μg/mL and 0.60 μg/mL in urine and plasma samples respectively. In both cases the coefficients of variation were lower than 6.5%, and the recoveries ranged betwe…
On the spectral intermediate at 440 nm formed during mixed function substrate oxidation.
1974
Abstract The spectral shoulder formed at 440 nm in microsomes oxidising hexobarbital and other drugs has been investigated and some of its properties characterised. Hexobarbital, pentobarbital, ethylmorphine and barbital produce this shoulder, while acetanilide, aniline, desmethylimipramine, imipramine, metyrapone and SKF 525-A do not. The formation of the 440 nm shoulder depends on the presence of NADPH and oxygen and is reduced in size when NADH is also present. At saturating substrate concentrations the size of the 440 nm shoulder is correlated to the cytochrome P-450 content. The hexobarbital induced shoulder can be inhibited by drug metabolism inhibitors such as metyrapone, imipramine …
4-Aminopyridine antagonizes the inhibitory effect of pentobarbital on acetylcholine release in the heart
1980
Effects of pentobarbital on acetylcholine (ACh) release, force of contraction and nervous conduction were studied in isolated heart preparations and in cervical vagus nerves, respectively. 4-Aminopyridine and tetracaine were used as pharmacological tools to eludicate the mode of action of pentobarbital. 1. 4-Aminopyridine (10−4 M) markedly increased the overflow of ACh from the isolated chicken heart evoked by electrical stimulation (1–50 Hz, 1 ms, 40 V) of the cervical vagus nerves. This effect of 4-aminopyridine was highest at low frequencies of stimulation (+ 226% at 1 Hz) and declined with increasing frequencies to reach a minimum augmentation of 22% at 30 Hz. 2. Pentobarbital and tetra…
Comparison of the effects of valproate, ethosuximide, phenytoin, and pentobarbital on cerebral energy metabolism in the rat.
1987
The acute effects of valproate (200 and 400 mg/kg), ethosuximide (200 and 400 mg/kg), phenytoin (25 and 50 mg/kg), and pentobarbital (30 and 60 mg/kg) on cerebral energy metabolism of rats were studied by measuring the cerebral content of energy metabolites and by evaluating the rate of metabolite utilization following decapitation. The treatments did not affect the levels of phosphocreatine (PCr), ATP, ADP, and AMP, but did enhance the glycogen or glucose stores. Pentobarbital induced a decrease in lactate, whereas valproate led to a decrease in pyruvate and an increase in lactate. Calculation of the metabolite fluxes after decapitation showed that all treatments delayed the rate of ATP ut…
Splenic blood flow and intrasplenic flow distribution in rats
1977
In 75 rats, anesthetized with pentobarbital and breathing spontaneously, regional splenic blood flow (rSBF) was measured by means of the85Kr(β)-clearance technique after an intraaortic slug injection of the dissolved indicator. In the normal and undisturbed spleen in situ rSBF is linearly related to the mean arterial blood pressure (MABP) within the range of 30–140 mm Hg. Mean rSBF is 0.71 ml/g/min, the mean arterial blood pressure being 105 mm Hg. In normal rats rSBF decreases significantly with increasing body weight or age. After total obstruction of the open circulation by application of rigid spherocytes, mean rSBF is reduced to 0.26 ml/g/min and is independent of the mean arterial blo…
Modification of depressant and disinhibitory action of flurazepam during short term treatment in the rat
1972
Employing a fixed-interval schedule of reinforcement (temporal discrimination), alternated punished (fixed-ratio) and unpunished (variable-ratio) schedules of reinforcement, a Conditioned Avoidance Response, and studying its interaction with Pentobarbital on general anaesthesia, it has been shown that flurazepam hydrochloride after a single treatment induces very intense depressant effects and slight disinhibitory effects. Short term treatment at longer than daily intervals reduces the depressant effect and unmasks the disinhibitory effect. The phenomenon is probably caused by selective tolerance concerning the depressant action. The results are discussed from the point of view of the signi…
Kavapyrone enriched extract fromPiper methysticum as modulator of the GABA binding site in different regions of rat brain
1994
Regional differences in the modulation of [3H] muscimol binding to GABAA receptor complexes by kavapyrones, compounds of the rhizome of the plant Piper methysticum which possess sedative activity, were demonstrated using membrane fractions obtained from target brain centers of kavapyrone action: hippocampus (HIP), amygdala (AMY) and medulla oblongata (MED), and from brain centers outside the main kavapyrone effects as frontal cortex (FC) and cerebellum (CER). The kava extract enhanced the binding of [3H] muscimol in a concentration-dependent manner with maximal potentiation of 358% over control in HIP followed by AMY and MED (main target brain centers). Minimal stimulation was observed in C…
Die Wirkung von Thiopental-Natrium und Pentobarbital-Natrium auf die Nierengef��e von M�usen
1957
The action of intravenous injections of pentobarbital and of thiopental on the blood pressure and on the vascular tone in the cortex of the kidney has been studied in albino mice. Pentobarbital caused a pronounced decrease of the filling of blood vessels in the cortex of kidneys together with a long-lasting anaesthesia and a long lasting fall of blood pressure. Thiopental, on the other hand, was less effective on the filling of blood vessels, while its narcotic effect was small and the fall of blood pressure less pronounced. The results indicate that both substances increased the vascular tone in the cortex of the kidney.