scholarly journals Synthesis of Some Novel Derivatives of 2-(9H-purin-6-ylsulfanyl) Acetohydrazide as Potential Antithyroid Agents

2017 ◽  
Vol 56 (4) ◽  
Author(s):  
Ismat Fatima ◽  
Munawar A. Munawar ◽  
Waqar Nasir ◽  
Misbahul A. Khan ◽  
Affia Tasneem ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Male Wistar Rats ◽  
Antithyroid Agents ◽  
Derivatives Of

Some novel derivatives of 2-(9<em>H</em>-Purin-6-ylsulfanyl)acetohydrazide were synthesized by reacting it with respective aldehydes in ethanol. The antithyroid effect of these compounds was ascertained <em>in vitro</em> by studying their complexation with iodine spectrophotometrically. <em>In vivo</em>, the hormonal as well as histological variations in male Wistar rats demonstrated significant antithyroid potential (p ≤ 0.05) of these compounds.

Concomitant release of sialic acids and calcium by neuraminidase from rat aorta in situ

1988 ◽  
Vol 235 (1279) ◽  
pp. 139-144 ◽  
Keyword(s):  
Sialic Acid ◽  
Wistar Rats ◽  
Rat Aorta ◽  
Sialic Acids ◽  
Molar Ratio ◽  
Male Wistar Rats

Male Wistar rats were heparinized and killed with pentobarbital. The upper and lower ends of the aortae were cannulated and the blood was washed out with saline until the washings contained calcium and sialic-acid-reacting material at minimal concentrations. The aortae were perfused with neuraminidase for 15 min. This caused the appearance of calcium as well as of sialic acids in the perfusate in total amounts of about 5.3 nmol and about 3.6 nmol per aorta respectively. The molar ratio of about 1.5 is sufficiently close to that determined for the association of calcium with sialic acids in vitro to suggest that their association is similar in vivo .

scholarly journals CUR-CA-THIONE: A NOVEL CURCUMIN CONCOCTION WITH ENHANCED WATER SOLUBILITY AND BRAIN BIO-AVAILABILITY

2016 ◽  
Vol 8 (12) ◽  
pp. 265 ◽  
Author(s):  
Devang Y. Shelat ◽  
Sanjeev R Acharya
Keyword(s):  
Wistar Rats ◽  
Water Solubility ◽  
Release Kinetics ◽  
Entrapment Efficiency ◽  
Systemic Circulation ◽  
Oral Route ◽  
Male Wistar Rats ◽  
Dialysis Bag

<p><strong>Objective: </strong>Curcumin, is widely studied as a potential drug in treating various disorders but lacks applicability due to poor water solubility and tissue bioavailability. The main objective of the study was to develop a formulation of curcumin that has enhanced water solubility and brain bioavailability.</p><p><strong>Methods: </strong>A curcumin concoction was prepared using solvent evaporation technique taking casein and glutathione as vectors. Various process parameters were identified namely time, temperature, pH and vector while formulation parameters included drug entrapment, anti-oxidant activity, and water solubility. The concoctions were evaluated for <em>in vitro</em> release kinetics at three pH i.e. 1.2, 4.5 and 6.2 at six-time intervals i.e. 10, 20, 30, 40, 60, 120 min using dialysis bag membrane. The same kinetics was further validated using same time points with wistar rats and giving concoction at a single dose of 2 g/kg via the oral route.</p><p><strong>Results: </strong>A concoction i.e. CUR-CA-THIONE having significant entrapment efficiency (77.83%, 97.75%, 90.19%), water solubility (40, 350 and 45 times than normal curcumin) and DPPH activity (IC<sub>50</sub>: 28.91, 25.07 and 27.89) was evaluated in concoctions CUR-CA-THIONE-T.1, CUR-CA-THIONE-T.2 and CUR-CA-THIONE-T.3 respectively. These formulations were then carried out for <em>in vitro</em> release profile at different pH with average release obtained between 20-30 min. <em>In vivo</em> kinetics was studied by isolating tissues like brain, liver, lung, kidney and spleen in male wistar rats and maximum brain bioavailability was observed for CUR-CA-THIONE-T.3 at 30 min with 75 ng/g of brain tissue.</p><p><strong>Conclusion: </strong>The experiment helps in concluding that CUR-CA-THIONE has improved its water solubility and is able to by-pass systemic circulation to targeted activity.</p>

scholarly journals Endothelium/Nitric Oxide Mediates the Vasorelaxant and Antihypertensive Effects of the Aqueous Extract from the Stem Bark ofMammea africanaSabine (Guttiferae)

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
Elvine Pami Nguelefack-Mbuyo ◽  
Alain Bertrand Dongmo ◽  
Télesphore Benoît Nguelefack ◽  
Albert Kamanyi ◽  
Pierre Kamtchouing ◽  
...  
Keyword(s):  
Aqueous Extract ◽  
Response Curve ◽  
Wistar Rats ◽  
Antihypertensive Effect ◽  
Stem Bark ◽  
Male Wistar Rats ◽  
Vasorelaxant Activity ◽  
Concentration Response Curve

This study evaluates the vasorelaxant and antihypertensive effects of the aqueous extract from the stem bark ofM. africana(AEMA). AEMA was testedin vitroon intact or endothelium-denuded rats’ aorta rings precontracted with KCl or norepinephrine in absence or in presence of L-NAME or glibenclamide. The effect of a single concentration (300 μg/mL) of AEMA was also examined on the concentration-response curve of KCl.In vivo, the antihypertensive effects of AEMA (200 mg/kg/day) were evaluated in male Wistar rats treated with L-NAME (40 mg/kg/day) for 4 weeks. AEMA relaxed aorta rings precontracted with NE or KCl with respective EC50 values of 0.36 μg/mL and 197.60 μg/mL. The destruction of endothelium or pretreatment of aorta rings with L-NAME shifted the EC50 of AEMA from 0.36 μg/mL to 40.65 μg/mL and 20.20 μg/mL, respectively. The vasorelaxant activity ofM. africanawas significantly inhibited in presence of glibenclamide. AEMA also significantly inhibited the concentration-response curve of KCl. Administered orally, AEMA induced acute and chronic antihypertensive effects and normalized renal NO level. These results show that the vasorelaxant activity of AEMA might be mediated by the activation of the NO-cGMP-ATP-dependent potassium channels pathway and might predominantly account for its antihypertensive effect.

The irreversible binding of benzo[a]pyrene to rat liver macromolecules in vivo and in vitro: Effects of agents that influence benzo[a]pyrene metabolism

1979 ◽  
Vol 57 (11) ◽  
pp. 1238-1245 ◽  
Author(s):  
L. S. Gontovnick ◽  
S. Ng ◽  
G. D. Bellward
Keyword(s):  
Wistar Rats ◽  
Methadone Treatment ◽  
Intraperitoneal Administration ◽  
Time Dependent ◽  
Diethyl Maleate ◽  
Irreversible Binding ◽  
Male Wistar Rats ◽  
In Vitro Effects

The present study was carried out to determine the effects of agents that influence benzo[a]-pyrene(BP)metabolism in vitro on the irreversible binding of BP to rat hepatic macromolecules in vivo. The irreversible binding of [3H]BP was found to be both dose and time dependent after its intraperitoneal administration to male Wistar rats. The SKF 525-A, at doses of 50 and 75 mg/kg, ip, 3 h before BP, decreased the level of binding from control by 31 and 34%, respectively. At 35 mg/kg, SKF 525-A had no effect. Diethyl maleate (0.6 mL/kg, ip) and cysteine (150 mg/kg, ip), 30 and 5 min before BP, respectively, did not alter the binding of BP from control. Oral methadone treatment, previously shown to increase selectively epoxide hydrase activity in male Wistar rats, also failed to alter the amount of BP bound to hepatic macromolecules. 3-Methylcholanthrene (20 mg/kg per day, ip, for 2 days) administered 24 h before BP, decreased the level of binding from control by.30%. Parallel in vitro studies were carried out with the various agents used in vivo.

scholarly journals Identification of Compounds With Vasoactive Properties in a Pitaya Juice Extract (Stenocereus griseus)

2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 362-362
Author(s):  
Yadira Ramírez Rodríguez ◽  
Karina Robledo Márquez ◽  
Ricardo Espinosa Tanguma ◽  
Alejandra Medina Hernández ◽  
Francisco Bautista-Redonda ◽  
...  
Keyword(s):  
Phenolic Compounds ◽  
Wistar Rats ◽  
In Vitro Models ◽  
Physiological Solution ◽  
Action Mechanism ◽  
Vasodilator Effect ◽  
Funding Sources ◽  
Male Wistar Rats

Abstract Objectives The objective of this study is to identify the vasoactive compounds present in the pitaya juice extract (PJE) and evaluate its effect using in vivo and in vitro models. Methods First, the pitaya juice was obtained from the fruit of Stenocereus Griseus, centrifuged to obtain PJE. Six hundred mL of PJE was frozen until its use and other 600 mL was lyophilized and stored. The lyophilized PJE was analyzed by HPLC-PAD. The wavelengths for detection in the PAD system were 535 and 480 nm for betalains, and 370 and 280 nm for phenolic compounds. On the other hand, the vasoactive effect of PJE was evaluated in isolated rings of thoracic aortas, with (n = 5) and without endothelium (n = 5), of male Wistar rats (250–350 g) previously contracted with phenylephrine (10 mM to 10 μmol/L), followed by the administration of a concentration of 20 mg/mL of lyophilized PJE and 1 mL physiological solution, as a control (30 min of treatment). Results The profiling of lyophilized PJE by HPLC-PAD showed 16 types of betalains and 31 types of phenolic compounds, which will be analyzed by mass spectrometry. Isolated aortic rings (in presence and absence of the endothelium) administered with PJE showed 8-fold greater vasodilation compared to the control (54.3% ± 14.1 vs 6.7% ± 3.7), suggesting that the compounds present in the PJE may exert a vasodilator effect, of which its action mechanism will be investigated. Conclusions Pitaya juice extract contains vasoactive compounds such as betalains and phenolic compounds, which could be responsible for PJE exerting a vasodilator effect that was observed in assays of isolated rat aortic rings. Funding Sources 1. Consejo Nacional de Ciencia y Tecnología (CONACYT) 2. Instituto Potosino de Investigación Científica y Tecnológica A.C. (IPICYT).

scholarly journals Effect of Recrystallization Technique on Oral Bioavailability of Valsartan

2021 ◽  
Vol 11 (6) ◽  
pp. 88-93
Author(s):  
TP Rao ◽  
N. Nalluri
Keyword(s):  
Oral Bioavailability ◽  
Wistar Rats ◽  
Relative Bioavailability ◽  
Water Soluble ◽  
In Vitro Dissolution ◽  
Type I ◽  
Dissolution Properties ◽  
Male Wistar Rats

Valsartan (VAL) is a widely prescribed anti-hypertensive agent with angiotensin II type I receptor antagonistic activity. VAL belongs to BCS class II having a low and variable oral bioavailability (10-35%) and its absorption is dissolution rate limited. Recrystallization of VAL from different organic solvents improved VAL aqueous solubility and thereby in vitro dissolution properties. In this investigation in vivo oral bioavailability (BA) of VAL and its recrystallized products with methanol and ethanol (VMET and VETH respectively) solvents was evaluated in male Wistar rats. Also, a rapid, economical and reliable RP-HPLC-PDA method was developed for the estimation of VAL in rat plasma samples and validated according to ICH guidelines. Chromatographic separation was achieved on an Agilent eclipse C18 column (150×4.6mm, 5µ) with a mobile phase composition of 10mM ammonium acetate: acetonitrile (75:25%v/v) at a flow rate of 1.2 mL/min. The retention time of VAL was found to be 2.9 min and showed good linearity (R2>0.996) in the selected concentration range of 0.5-25µg/mL. A 2.9, 2.8 folds increase in Cmax and a relative bioavailability of 320, 305% was observed with VMET and VETH respectively, when compared to that of untreated VAL. Thus it can be inferred that recrystallization is easy and economical technique for enhancing the pharmaceutical properties like solubility, dissolution properties and oral BA of poorly water soluble drugs like VAL. Keywords: Bioanalytical method, Bioavailability, Male Wistar rats, Valsartan, Recrystallization

scholarly journals TOPICAL DELIVERY OF QUERCETIN LOADED TRANSFERSOMES FOR WOUND TREATMENT: IN VITRO AND IN VIVO EVALUATION

2021 ◽  
pp. 189-197
Author(s):  
MARWA ABDALLAH ◽  
DEMIANA I. NESEEM ◽  
OMAIMA N. ELGAZAYERLY ◽  
ALY A. ABDELBARY
Keyword(s):  
Wistar Rats ◽  
Spherical Shape ◽  
The Other ◽  
Wound Treatment ◽  
In Vivo Evaluation ◽  
Skin Deposition ◽  
Significant Difference ◽  
Male Wistar Rats

Objective: To design topical Quercetin (Qc)-loaded transfersomes (TFs) for wound treatment. Methods: Qc-loaded TFs were prepared by thin-film hydration technique using 2241full factorial design and the optimum formula was selected. In vivo skin, deposition and cutaneous wound induction studies were performed for four groups of male wistar rats. At the end of the experiment, biochemical parameters were measured in the healed tissues (total proteins (TP), total antioxidant capacity (TAC), glutathione reductase (GSH), nitric oxide (NO), and malonaldehyde (MDA). Two in vivo histopathological experiments using male wistar rats were performed; the first study was done for the healed tissues of the above experiment and the second was to confirm the safety of formulations. Results: Qc optimum TFs (F6) showed EE% of 91.1%, PS of 695.35 nm, PDI of 0.592, and ZP of-11.1 mV, and spherical shape. In vivo skin deposition study showed that drug percentage retained in the skin from Qc optimum TFs was significantly higher than that from Qc suspension and Qc liposomes (p<0.05). There was no significant difference in the values of TP, TAC and MDA between the treated groups (p>0.05). GSH in TFs treated groups was significantly higher than the other groups (p<0.05) while NO in TFs treated groups was significantly lower than the other treated groups (p<0.05). Histopathological experiments showed that wounds treated by TFs healed better than those treated by both liposomes and Qc suspension. Conclusion: Qc-loaded TFs can be used as successful drug-delivery system for wound healing.

Effects of amiodarone on 5′-deiodination of thyroxine to tri-iodothyronine in rat myocardium

1989 ◽  
Vol 121 (3) ◽  
pp. 431-434 ◽  
Author(s):  
J. A. Ceppi ◽  
A. A. Zaninovich
Keyword(s):  
Body Weight ◽  
Phosphate Buffer ◽  
Wistar Rats ◽  
Type Ii ◽  
Rat Myocardium ◽  
Iopanoic Acid ◽  
Male Wistar Rats ◽  
Expected Increase

ABSTRACT The present work studied the effects of amiodarone (AMD) and iopanoic acid (IA) on the conversion of thyroxine (T4) to tri-iodothyronine (T3) by rat myocardium. In vivo: male Wistar rats weighing 200–250 g were injected i.p. with AMD (2·5 mg/100 g body weight per day for 12 days) or IA (5 mg/100 g body weight every 12 h for 72 h). Hearts were then removed and processed as in the in-vitro studies. In vitro: hearts were homogenized in Krebs–Ringer phosphate buffer (pH 7·4) and AMD (0·1 mmol/l) or IA (10 mmol/l) plus dithiothreitol (8 mmol/l) and 0·01 μCi [125I]T4 or [125I]T3 were added. After incubation for 2 h at 37 °C, radioactive compounds were identified by paper chromatography. Both AMD and IA given in vivo blocked T4 to T3 conversion significantly (P<0·005). When added in vitro, AMD failed to inhibit T4 deiodination to T3 whereas IA induced a significant (P<0·005) decrease in T3 generation. Deiodination of [125I]T3 by heart homogenates was not altered by AMD or IA. While the expected increase in circulating T4 (P< 0·001) and decrease in T3 (P< 0·001) did occur after AMD or IA treatment, plasma TSH in AMD-treated rats was decreased (P<0·001), while in IA-treated animals it was increased (P< 0·001), thus indicating that AMD did not inhibit pituitary type-II 5′-monodeiodinase. In summary, these data suggest that the hypometabolism induced by AMD in rat myocardium through a decrease in the supply of T3 is not responsible for the anti-arrhythmic activity of this drug since IA, which is not an anti-arrhythmic compound, elicited the same effect on cardiac T3. It follows that inhibition of 5′-deiodinase and the anti-arrhythmic activity of AMD are independent properties. Journal of Endocrinology (1989) 121, 431–434

EFFECTS OF CYPROTERONE AND CYPROTERONE ACETATE ON THE ADRENAL GLAND IN THE RAT: STUDIES IN VIVO AND IN VITRO

1979 ◽  
Vol 80 (2) ◽  
pp. 229-NP ◽  
Author(s):  
N. S. PANESAR ◽  
D. G. HERRIES ◽  
S. R. STITCH
Keyword(s):  
Plasma Concentration ◽  
Cyproterone Acetate ◽  
Wistar Rats ◽  
Indirect Evidence ◽  
Hydroxysteroid Dehydrogenase ◽  
Reaction Rates ◽  
Steroid Biosynthesis ◽  
Male Wistar Rats

Male Wistar rats were treated for three weeks with cyproterone (1·7 or 5·1 mg/day) or cyproterone acetate (2 or 6 mg/day). The adrenal weights of animals treated with either dose of cyproterone acetate were significantly less (P < 0·001) than those of untreated animals. In contrast, the adrenal weights of animals treated with cyproterone did not differ from those of the controls. The concentrations of corticosterone in the plasma were significantly less (P < 0·001) in both groups treated with cyproterone acetate compared with those of the controls; only the higher dose of cyproterone reduced the plasma concentration of corticosterone (P < 0·001). Cyproterone acetate inhibited the rat adrenal 3β-hydroxysteroid dehydrogenase–5-ene,4-ene-isomerase complex in vitro, with both pregnenolone and dehydroepiandrosterone as substrates. Analysis of the reaction rates suggested an uncompetitive mode of inhibition. These results suggest that in rats the antiandrogens cyproterone and cyproterone acetate may provoke adrenal insufficiency by inhibition of steroid biosynthesis. Furthermore, indirect evidence from the mass and morphology of the adrenal suggests that cyproterone acetate may also suppress production or secretion of ACTH by the pituitary gland.

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