bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effects of neostigmine on the response of the rat anococcygeus muscle to field stimulation are not a consequence of Cholinesterase inhibition
Authors: Smith J A , Spriggs T L B 
Published: April 2011

Abstract
Neostigmine (5 times 10−7 to 5 times 10−6 M) and physostigmine (10−5 M) each augment the responses of the rat anococcygeus muscle to field stimulation whereas iso-OMPA (5 times 10−6 to 5 times 10−4 M) or BW 62c47 (5 times 10−7 to 5 times 10−5 M) do not. At a concentration of 10−5 M, neostigmine, BW 62c47 and iso-OMPA respectively produced a 48, 50 and 68% inhibition of cholinesterase activity in homogenates of anococcygeus muscle. The ED50 for cholinesterase inhibition by neostigmine (1.4 times 10−5 M) is approximately 15 fold greater than the ED50 for the augmentation of the response to field stimulation (9.5 times 10−7 M). It is concluded that the action of neostigmine in augmenting the response of the rat anococcygeus muscle to field stimulation is not a consequence of cholinesterase inhibition even though stimulation of muscarinic receptors is implicated.
Particulate contamination in ampoules
Authors: Alexander D M , Veltman A M 
Published: April 2011

Abstract
The particulate contamination in 19 formulations of solutions in ampoules supplied by eight South African manufacturers, thirty-three batches in all, was analysed using a HIAC PC 320 light blockage particle analyser linked to a CMB 60 sensor. Results showed that the level of contamination was generally low and that, where comparisons could be made, manufacturers both of the ampoules and the solutions maintained similarly high standards. Problems in this field appeared to be related to the formulation or the quality of the raw material.
The effect of some benzimidazoles on the disposition of antipyrine and tolbutamide from the rat isolated perfused liver
Authors: Ward S A , Mihaly G W , Tjia J F , Back D J 
Published: April 2011

Abstract
The anthelmintic benzimidazoles, mebendazole, albendazole and flubendazole have been screened for any propensity to alter the disposition of antipyrine and tolbutamide in the rat isolated perfused liver preparation. The benzimidazoles were added as a 2.5 mg bolus dose into the perfusate reservoir 5 min before the administration of either antipyrine or tolbutamide. Neither mebendazole or albendazole produced any significant effect on the pharmacokinetics of either of the substrate drugs. In contrast, flubendazole significantly decreased the clearance of antipyrine (by 40%) indicating inhibition of mixed function oxidase activity. However, flubendazole did not alter the disposition of tolbutamide. The results suggest that not all benzimidazoles inhibit hepatic drug metabolizing enzymes and that different forms of cytochrome P-450 are involved in the metabolism of antipyrine and tolbutamide.
Effect of implanted ethylene-vinyl alcohol copolymer matrices containing 5-fluorouracil on Ehrlich ascites carcinoma
Authors: Miyazaki Shozo , Takeuchi Shigemi , Sugiyama Mieko , Takada Masahiko , Hosokawa Masuo , Koga Yutaka , Kobayashi Hiroshi 
Published: April 2011

Abstract
The antitumour activity of ethylene-vinyl alcohol (EVAl) copolymer matrices containing 5-fluorouracil (5-FU) was evaluated against Ehrlich ascites carcinoma in mice. A prolongation of the life-span of tumour-bearing mice following intraperitoneal implantation of therapeutic matrices was noted. These results indicated that EVAl matrices containing 5-FU may be effective in cancer chemotherapy. Matrices composed of EVAl copolymer could be useful vehicles for implanted, inserted, or surface-applied delivery systems for anticancer agents.
Phthalic acid esters inhibit arachidonate metabolism by rat peritoneal leucocytes
Authors: Tavares I A , Vine N D 
Published: April 2011

Abstract
Phthalic acid esters concentration-dependently inhibited the formation of both cyclo-oxygenase and lipoxygenase arachidonate products by rat peritoneal leucocytes. Phthalates are extracted by human transfusion blood stored in pvc bags, and might similarly affect the blood cells when administered to patients.
In-vivo metabolism in the rat and mouse of antrafenine to 1- m-trifluoromethylphenylpiperazine
Authors: Caccia S , Conti I , Notarnicola A 
Published: April 2011

Abstract
The analgesic antrafenine forms 1- m-trifluoromethylphenylpiperazine (mCF3PP) during its biotransformation in the rat and mouse. At least 14 and 3% of an antrafenine dose (25 mg kg−1 p.o.) reaches the systemic circulation as mCF3PP in the mouse and rat respectively. The metabolite easily enters the brain, reaching concentrations several times those in body fluids. This, together with the fact that mCF3PP is known to produce several pharmacological effects compatible with a stimulatory action on 5-hydroxytryptamine postsynaptic receptors, suggests that this metabolite may contribute to the parent drug's pharmacological effects.
Photon correlation spectroscopy of surface active cationic drugs
Authors: Atherton A D , Barry B W 
Published: April 2011

Abstract
Photon correlation spectroscopy (PCS) has been used to examine the aggregation in aqueous NaCl solution of a series of antidepressant and antihistamine drugs (hydrochlorides of imipramine, clomipramine, amitriptyline, butriptyline, protriptyline, doxepin, dothiepin, iprindole, diphenhydramine, bromodiphenhydramine, orphenadrine) propranolol hydrochloride and propantheline bromide. Critical micelle concentrations were measured by surface tension and PCS. Micellar sizes were investigated as functions of drug structure and drug and NaCl concentration. Generally, antidepressants formed the largest micelles. We propose that the antidepressants aggregate in a similar fashion to the phenothiazines by stacking with size increasing by addition of single monomers to stacks and by addition of more stacks to the aggregate.
19F NMR spectroscopy study of the metabolites of flucloxacillin in rat urine
Authors: Everett J R , Jennings K , Woodnutt G 
Published: April 2011

Abstract
19F NMR spectroscopy was used to monitor the metabolites of flucloxacillin in the urine of a rat dosed with its sodium salt. 19F NMR signals were detected and quantified from flucloxacillin and three metabolites. The 19F NMR method involves minimal sample preparation and is free from interference by endogenous urine components. High-field spin-echo 1H NMR spectroscopy and HPLC were used to confirm the results.
The sustained release of pyrimethamine base or pyrimethamine pamoate from a biodegradable injectable depot preparation in mice
Authors: Coleman M D , Mihaly G W , Ward S A , Edwards G , Howells R E , Breckenridge A M 
Published: April 2011

Abstract
The pharmacokinetics and mass fate in mice, of pyrimethamine (425 mg kg−1 s.o.) administered subcutaneously either as the base (BASE) or the pamoate salt (PAM) in an injectable oil mixture (benzyl benzoate-peanut oil 50:50 v/v) have been evaluated. Maximum measured plasma pyrimethamine levels after BASE were attained within 24 h, and were twice as high as after PAM. 25% of animals dosed with BASE died; among the survivors plasma drug levels fell rapidly below the minimum inhibitory concentration (MIC) for Plasmodium berghei (100–200 ng ml−1) by 5 weeks. In contrast, no mice dosed with PAM died and plasma levels were sustained above the MIC for 13 weeks, drug still being detectable in plasma after four months. Overall, there was no significant difference between areas under the curve from zero time to the time of the final sampling of pyrimethamine following PAM or BASE. The rapid initial elimination of 14C-radioactivity (2&#x006d;̇64 ± 0&#x006d;̇47% dose day−1 over 4 weeks) seen after dosage with [14C]BASE reflected the plasma disposition of pyrimethamine in the mice dosed with BASE. 90% of the excreted 14C was eliminated by one month by which time less than 1% (0&#x006d;̇03 ± 0&#x006d;̇02%) of the [14C]BASE was recovered from the injection site. Both BASE and [14C]BASE studies suggest that exhaustion of this preparation occurred by 7 weeks. Excretion of 14C-radioactivity after [14C]PAM was gradual and sustained with a low mean daily rate, that was maintained throughout the study i.e. 1&#x006d;̇21 ± 0&#x006d;̇17% day−1 (4 weeks), 0&#x006d;̇88 ± 0&#x006d;̇28% day−1 (8 weeks), 0&#x006d;̇5 ± 0&#x006d;̇31% day−1 (12 weeks), 0&#x006d;̇42 ± 0&#x006d;̇27% day−1 (16 weeks). At the end of the study, 7&#x006d;̇11 ± 1&#x006d;̇90% of the [14C]PAM remained in the dose site. No visible tissue reactions were observed to either preparation. Overall recovery of radioactivity was 85&#x006d;̇00 ± 11&#x006d;̇31% for both [14C]PAM and [14C]BASE. These studies indicate that the PAM preparation is worthy of further long term evaluation.
Magnesium ions and oxytocin sensitivity of the male mouse anococcygeus
Authors: Gibson A 
Published: April 2011

Abstract
The sensitivity of the mouse anococcygeus to contraction by oxytocin was shown to be Mg2+-dependent. Decreasing [Mg2+]0 from the optimal concentration of 1 to 0 mM caused a 20-fold parallel rightward displacement of the oxytocin dose-response curve. Contractions to oxytocin-related peptides (Arg-vasotocin, Arg-vasopressin and Lys-vasopressin) were also Mg2+-dependent, but those to other drugs (carbachol, methoxamine and thyrotrophin releasing hormone) were not. The onset of the potentiating effect of Mg2+ was rapid, full potentiation occurring within 70 s. 1-Deaminopenicillamine 8-ornithine-vasotocin produced competitive antagonism of responses to oxytocin, but was more potent in the absence (pA2 = 8&#x006d;̇01) than in the presence of Mg2+ (1 mM; pA2 = 7&#x006d;̇52). Thus, physiological concentrations of [Mg2+]0 enhanced oxytocin agonist potency but decreased oxytocin antagonist potency; possible mechanisms are discussed.
An investigation of the structural changes occurring in a cetostearyl alcohol/cetrimide/water gel after prolonged low temperature (4°C) storage
Authors: Patel H K , Rowe R C , McMahon J , Stewart R F 
Published: April 2011

Abstract
Structural changes in a ternary gel prepared using the mixed emulsifier system of cetrimide and cetostearyl alcohol after prolonged low temperature (4°C) storage have been studied using freeze-etch transmission electron microscopy and other techniques. The system changed from an opaque smooth gel of high viscosity, low conductivity and low free water, to a pearlescent milky lotion of low viscosity, high conductivity and high free water. Subsequent equilibration of the thinned system to room temperature (25°C) over 48 h produced an opaque granular gel of similar consistency, but slightly higher conductivity and higher free water than the initial sample. Microscopical examination by both differential interference contrast and freeze-etch electron microscopy showed the system changed from one consisting of a liquid crystalline network localized around cetostearyl alcohol particles, to a system consisting of large waxy plates coexisting with some residual liquid crystalline network. A supportive mechanism for the thinning of the ternary gel at prolonged low temperature storage has been inferred by comparing data with that produced by other workers studying the fusion of phospholipid membranes considered to be morphologically similar to the liquid crystalline network observed in this ternary gel.
Further assessment of glunicate hypolipidaemic activity in the rat
Authors: Renzetti Anna Rita , Criscuoli Marco , Subissi Alessandro 
Published: April 2011

Abstract
The hypolipidaemic activity of glunicate administered orally to rats has been further evaluated. In the fasted normolipidaemic rat, glunicate, in single doses of 10&#x006d;̇300 mg kg−1 (as nicotinic acid equivalents), exerted a dose-dependent reduction of plasma triglycerides and cholesterol. At the lower doses, the HDL: total cholesterol ratio was enhanced, but at higher doses it was depressed. Similar results were obtained in the fasted obese Zucker rat, but the acute effects of glunicate seemed less marked in this strain. When the same doses of glunicate were given for 7–8 consecutive days no alteration of the plasma lipid pattern was observed, the reason being that the hypocholesterolaemic action of single doses of glunicate is reduced or abolished in fed animals; this was not due to pharmacokinetic factors depending on feeding. The same lack of hypocholesterolaemic action in fed animals occurred with nicotinic acid.
Age-related changes in sorbitol dehydrogenase activity of rat brain, liver, kidney and eye
Authors: Cao Danh H , Benedetti M Strolin , Dostert P 
Published: April 2011

Abstract
Sorbitol dehydrogenase (SDH) activity was measured in whole brain, different brain areas, liver, kidney and eye of old rats (23–26 months) and compared with matched animals (3 months). A significant increase in SDH activity was found in whole brain (34%) of old rats, as well as in all brain areas studied: brainstem (59%), hypothalamus (38%), cerebral cortex (35%), striatum (30%), midbrain (27%), hippocampus (27%) and cerebellum (19%). The increase in SDH activity in brain of old rats is due to Vmax. These results do not favour an accumulation of sorbitol in brain of old rats. A significant decrease (36%) in SDH activity was found in kidney and no significant change in liver and eye of old rats when compared with young rats. Our previous and present results suggest that an accumulation of sorbitol might occur in some tissues of old rats, particularly in the eye, and cause cataract formation.
Interaction between clonidine and histamine on the guinea-pig isolated trachea
Authors: Floch A , Advenier C 
Published: April 2011

Abstract
In experiments on guinea-pig isolated tracheal spirals, clonidine, in concentrations of 10−6 to 3 times 10−4 M. had a contracting effect which was strongly inhibited by prazosin but not significantly modified by yohimbine. Moreover, clonidine (3 times 10−5 to 3 times 10−4 M) potentiated histamine-induced contractions; this latter effect was inhibited specifically by α1-adrenoceptor antagonists (e.g. prazosin, AR-C 239) but unmodified by yohimbine, nicardipine or agents acting on the arachidonic acid cascade. It would therefore appear that clonidine in high concentrations contracts the guinea-pig trachea by stimulating α1-adrenoceptors and that, contrary to what has been reported with other animal species, notably the dog, the guinea-pig trachea is devoid of α2-adrenoceptors that mediate contractions.
Prostaglandin D2-induced potentiation of hexobarbitone hypnosis in rats: role of 5-hydroxytryptamine
Authors: Bhattacharya S K , Parmar S S 
Published: April 2011

Abstract
Prostaglandin D2 (PGD2) produced a dose-related increase in the duration and incidence of induction of sleep induced by hexobarbitone, in rats. Pretreatment with pharmacological agents known to reduce selectively brain 5-hydroxytryptaminergic activity, significantly inhibited PGD2-induced potentiation of hexobarbitone, indicating that this potentiation is mediated by 5-hydroxytryptamine.
Amphetamine-induced circling behaviour in MPTP-lesioned mice
Authors: Fung Yiu K , Troxel Charles E 
Published: April 2011

Abstract
This study was designed to examine the effect of intra-striatal administration of MPTP on (+)-amphetamine-induced circling behaviour in mice. The results demonstrate that (+)-amphetamine elicits circling behaviour in MPTP-lesioned animals. MPTP produced a 70% depletion of striatal dopamine concentration.
Inhibition of rabbit cardiac adenylate cyclase by theophylline
Authors: Hopwood Alexandra M , Harding Sian E , Harris Peter 
Published: April 2011

Abstract
Theophylline inhibits basal adenylate cyclase activity as well as cyclase stimulated by sodium chloride, sodium fluoride, GTP or 5′-guanylimidodiphosphate. This inhibition is dose-dependent and shows non-competitive inhibition, with respect to MgATP. The presence of adenosine deaminase does not alter the effect of theophylline. The inhibition produced by theophylline is not additive with that due to 2′-deoxyadenosine 3′-monophosphate (a P-site agonist). It is suggested that theophylline may act at the P-site to reduce adenylate cyclase activity.
Ascorbic acid antagonizes the behavioural effects of LSD in cats
Authors: Trulson Michael E , Crisp Terriann , Henderson Leslie J 
Published: April 2011

Abstract
Pretreatment with ascorbic acid (500 mg kg−1 i.p.) antagonized the behavioural effects of lysergic acid diethylamide (LSD) and apomorphine, but not 5-methoxy-N,N-dimethyltryptamine, in cats. The data support the hypothesis that these behavioural effects in cats are due to drug action at both 5-HT and dopamine receptors, and that the action of LSD at dopamine receptors is modulated by ascorbic acid.
A hypothesis for the mode of action of anti-rheumatic drugs in a model of cartilage destruction
Authors: Willoughby D A , Al-Duaij A , de Brito F , Sedgwick A D , Moore A R , Williams J D 
Published: April 2011

Abstract
We have been using as a model rats and mice with air pouches which develop lining cells closely resembling synovium (Edwards et al 1982; Sedgwick et al 1983). These pouches when sufficiently mature, i.e. 6 days, will respond to a variety of stimuli both immune and non-immune with long lasting exudates containing many migrated leucocytes (Sedgwick et al 1983, 1984a).
We examined the breakdown of cartilage in both inflamed and non-inflamed pouches and have found that inflammation protected the rate of loss of proteoglycan from cartilage (Sedgwick et al 1984b. 1985; Willoughby et al 1985). Invariably the cartilage in the inflamed air pouch would float free in exudate while cartilage, in the non-inflamed pouch would adhere to the pouch wall in close proximity to the macrophages and fibroblasts of the lining cells. Unpublished findings from this department (de Brito) have shown that the presence of granulation tissue in close proximity to cartilage will speed proteoglycan loss.
Interaction of cyclosporin A with human lipoproteins
Authors: Sgoutas Demetrios , Macmahon Wendy , Love Ann , Jerkunica Ivanka 
Published: April 2011

Abstract
The ultracentrifugal fractionation of human serum after previous incubation with cyclosporin A showed that, in healthy fasting individuals, 8% of cyclosporin A was found in the very low density lipoproteins (VLDL), 31% in the low density lipoproteins (LDL), 46% in the high density lipoproteins (HDL) and 15% in the non-lipoprotein protein fraction. In non-fasted, healthy and in non-fasted, lipaemic individuals, 7 and 6% of cyclosporin A was found in chylomicrons, 9 and 13% in VLDL, 28 and 30% in LDL, 39 and 37% in HDL, and 12 and 13% in the non-lipoprotein protein fraction, respectively. In patients receiving cyclosporin A the distribution varied from 12 to 19% in VLDL, 21 to 28% in LDL, 33 to 43% in HDL, and 13 to 20% in non-lipoprotein proteins. The interaction between cyclosporin A and isolated normal human lipoproteins was also studied by ultrafiltration. All lipoproteins exhibited a non-saturable, low affinity, high capacity uptake for cyclosporin A. Analysis of the uptake by phospholipid vesicles showed a similar uptake, suggesting that cyclosporin A dissolves in the lipophilic portion of the lipoprotein molecule rather than being associated with specific binding sites.
The effects of new local anti-inflammatory steroids on leucocyte migration and prostanoid liberation in rats
Authors: Bird John , Lay John C , Lee Henry J 
Published: April 2011

Abstract
The local anti-inflammatory potency of steroid-21-oate esters derived from prednisolone was determined by cotton pellet granuloma bioassay. The doses which inhibited granuloma formation by 50% (ID50) were: prednisolone, 0.5 mg/pellet; methyl 20α-dihydroprednisolonate, 5.8 mg/pellet; methyl 20 β-dihydroprednisolonate, 1.2 mg/pellet; methyl 17,20α-acetonidodihydroprednisolonate, 6.0 mg/pellet. When administered at these equipotent local anti-inflammatory doses, only prednisolone depressed plasma corticosterone and promoted thymus involution. Prednisolone reduced neutrophil migration into saline-soaked polyester sponges and depressed the levels of 6-keto PGF1α, PGE2 and elastase in the sponge-induced inflammatory exudate. Methyl 20α- and 20β-dihydroprednisolonate had no effect on cell migration, but depressed the levels of 6-keto PGF1α and elastase. The liberation of 6-keto PGF1α, PGE2 and elastase and neutrophil migration were inhibited by methyl 17,20α- and β-acetonidodihydroprednisolonate, but the effect of the β-epimer on cell migration was transient. These data suggest that steroid acid esters which have local and topical anti-inflammatory properties exert their effect in a similar fashion to glucocorticoids with a ketol side-chain (e.g. prednisolone) with respect to liberation of prostaglandins and lysosomal enzymes. However, their effect on neutrophil migration was variable, depending on their structural features. Furthermore, the systemic effects of these new derivatives were drastically reduced indicating that they may be of potential benefit in prolonged treatment.
Mechanism of the inhibitory effect of thiopentone on stimulus-secretion coupling in chromaffin cells
Authors: Matsumoto Tomikichi , Sumikawa Koji , Kashimoto Takeshi 
Published: April 2011

Abstract
This study was undertaken to clarify the mechanism of action of thiopentone on stimulus-secretion coupling in cholinergic postsynaptic cells using cultured bovine adrenal chromaffin cells. Thiopentone (20–100 μm) inhibited carbachol-induced Ca2+ uptake into, and catecholamine release from, the cells in a concentration-dependent manner. The inhibition of catecholamine release was almost parallel to the inhibition of Ca2+ uptake. The inhibitory effect of thiopentone was not overcome by an increase in the concentration of carbachol, whereas that of alcuronium was. Contrary to the inhibition by diltiazem, which was reversed by increasing the Ca2+ concentration, the inhibition by thiopentone was not overcome by a high Ca2+ concentration. Compared with the inhibition of carbachol-induced catecholamine release, a higher concentration of thiopentone was required to inhibit high K+ (56 mM KCl)-induced catecholamine release (200 μm thiopentone exhibited 32% inhibition). The results suggest that thiopentone blocks the stimulus-secretion coupling in the chromaffin cells as a result of inhibiting Ca2+ uptake through nicotinic receptor-linked channels. The linkage between receptor stimulation and Ca2+ channel activation seems to be the process most susceptible to inhibition by the barbiturate.
Racemic and optically active trans 2,6-dimethyl analogues of the reversed ester of pethidine
Authors: ranch S K B , Casy A F , Cittern P , Madani A E 
Published: April 2011

Abstract
The preparation and stereochemical characterization of (±)-1, trans 2,6-trimethyl-4-phenyl-4-propionoxypiperidine hydrochloride and its (+)- and (−)-antipodes are described. The absolute configurations of the antipodes were established by X-ray analysis of the corresponding (−)-4-piperidinol hydrobromide. In antinociceptive tests on mice and rats, the (+)-2S,6S ester proved the more potent antipode by factors of at least 10 (rats) and 20 (mice), a result consistent with earlier proposals made about the probable uptake conformation of pethidine reversed esters at opioid receptors.
Antitumour effect of fibrinogen microspheres containing doxorubicin on Ehrlich ascites carcinoma
Authors: Miyazaki Shozo , Hashiguchi Norio , Yokouchi Chizuko , Takada Masahiko , Hou Wei-Min 
Published: April 2011

Abstract
The antitumour activity of fibrinogen microspheres containing doxorubicin has been evaluated against Ehrlich ascites carcinoma in mice in terms of changes in body weight and survival. Tumour cell injections were made on day 0 and microsphere injections on day 1, both intraperitoneally. The suppressive effect of the drug-containing microspheres on increase in body weight was higher than that of the free drug, and tumour-bearing mice given the microspheres lived longer than those given the free drug.