bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of pulmonary metabolites of prostaglandins E2 and F2α on guinea-pig respiratory tract
Authors: Lo Pia Yong 
Published: April 2011

Abstract
The effects of three pulmonary metabolites of prostaglandins E2 and F2α on the guinea-pig tracheal muscle in vitro and on lung resistance in vivo were investigated. Prostaglandin F2α, 13, 14-dihydro PGF2α and 13,14-dihydro 15-oxo PGF2α produced contractions on the tracheal muscle in vitro. 15-oxo PGF2α relaxed some tracheal preparations but stimulated others, the stimulant action having a threshold dose range some 10–25 times lower than the relaxant doses. Prostaglandin F2α and 13,14-dihydro PGF2α increased lung resistance in anaesthetized guinea-pigs. Prostaglandin E2 and its three pulmonary metabolites produced relaxation of guinea pig trachea in vitro and decreased lung resistance in vivo. All three metabolites were less active than PGE2 in both the systems. The in vitro effects of PGF2α and its metabolites were selectively blocked by polyphloretin phosphate.
Degradation of (—)-ephedrine in solution and during extraction with diethyl ether
Authors: Beckett A H , Jones G R , Hollingsbee D A 
Published: April 2011

Abstract
Significant losses occurred during the extraction of small quantities of ephedrine from aqueous media using either regular or analytical grades of diethyl ether. The losses were, at least in part, caused by reaction of the ephedrine with aldehydic impurities in the ether; three substituted oxazolidines were identified, using g.l.c. and g.l.c.-ms. These and one other oxazolidine were synthesized and characterized by g.l.c, g.l.c.-ms, nmr and infrared spectroscopy. Alternative mechanisms for ephedrine breakdown were considered. Ephedrine was separately oxidized by three different oxidizing agents and also irradiated by ultraviolet light; the products were characterized by g.l.c, g.l.c.-ms. A method for the purification of diethyl ether is recommended to minimize ephedrine breakdown.
Red cell cyanide
Authors: Vesey Cyril J , Wilson John 
Published: April 2011

Abstract
The amount of cyanide released on acidifying whole blood was much greater than the total from the plasma and red cells assayed separately, and varied directly with plasma thiocyanate concentrations. This artifactual formation of cyanide by whole blood was reduced by exposure to carbon monoxide. Incubation of haemolysates of washed red blood cells showed that optimum cyanide production from thiocyanate occurred at pH 4·5 with none at pH 7·4; spectrophotometric study confirmed the involvement of haemoglobin. It is doubtful whether this activity of haemoglobin is of normal physiological importance and it is probable that the evidence for the enzyme, ‘thiocyanate oxidase’ was based on this artifact of assay. Plasma cyanide is probably the metabolically relevant measurement, since the red blood cells act as a ‘cyanide sink’. Where values for whole blood cyanide are required we recommend separate assay of plasma and saline washed red blood cells.
Changes in muscarinic ligand binding to intestinal muscle strips produced by pre-exposure to hypotonic conditions
Authors: Elliott J M , Tayler P J , Young J M 
Published: April 2011

Abstract
The extent of the binding of [3H]propylbenzilylcholine mustard (3H-PrBCM) to muscarinic receptors in longitudinal muscle strips from guinea-pig small intestine is increased by nearly 50 % when the strips are preexposed to distilled water before measurement of 3H-PrBCM binding in Krebs-Henseleit solution. The apparent rate constant for 3H-PrBCM-receptor complex formation is more than double that of intact strips. The curves for the inhibition of 3H-PrBCM binding by methylatropinium bromide in normal and treated strips are superimposable, but, in contrast, distilled water pretreatment shifts the inhibition curve for carbachol to lower concentrations by a factor of 5–6. The inhibition curve for methyl-furmethide is also shifted, by a factor of approximately 4, but the effect on the curve for hexyltrimethylammonium (C6TMA) is slight. The relative inhibition produced by benzhexol in the two preparations was variable. Comparison of the rate of equilibration of benzhexol with muscarinic receptors in intact and in distilled water pretreated muscle indicates that this inconsistency is unlikely to be due to incomplete equilibration.
Modification by monoamine oxidase inhibitors of the analgesic, hypothermic and toxic actions of morphine and pethidine in mice
Authors: Botting Regina , Bower Susan , Eason C T , Hutson P H , Wells Linda 
Published: April 2011

Abstract
A single injection of phenelzine 100 mg kg−1 given 18 h before, decreased the analgesia and hypothermia induced by morphine, but potentiated the analgesic and hypothermic effects of pethidine, when the analgesics were administered either intraperitoneally or intracerebroventricularly. The modification of pethidine analgesia and hypothermia, but not morphine analgesia, was antagonized by methysergide (10 mg kg−1, s.c). The LD50 of pethidine, but not that of morphine, was 30–40 % lower in mice treated with phenelzine tranylcypromine or iproniazid 6 h before the test. The increased lethality of a single dose of pethidine induced by phenelzine was also prevented by methysergide. Pretreatment of mice with 100 mg kg−1 phenelzine was followed by a significant rise in both brain tryptophan and 5-hydroxytryptamine (5-HT) concentrations which lasted for 24 h. Therefore, the changes in pethidine effects could have been due to raised brain tryptophan and 5-HT concentrations.
Problems associated with analysis and interpretation of small molecule/macromolecule binding data
Authors: Plumbridge Terence W , Aarons Leon J , Brown Jeffrey R 
Published: April 2011

Abstract
In the analysis of binding data, arbitrary transformations such as the Scatchard plot, may give misleading estimates of the binding parameters. The statistically correct approach is to determine values of K and n by non-linear regression of the actual dependent variable against the actual independent variable. In the case of the spectrophotometric titration method the dependent variable is the absorbance and the independent variable is the composition of the drug/macromolecule mixture. The method relies on an accurate estimate of the extinction coefficient of the bound drug and this is best treated as a parameter to be estimated in the regression analysis. In testing models by data fits alone it is emphasized that whilst a model may be rejected if it does not fit the data, a good fit does not ensure uniqueness and confirmatory, independent evidence must be sought.
Effects of bromocriptine on adenylate cyclase and phosphodiesterase activities of rat striatum
Authors: Pagnini Giuseppe , Camanni Franco , Crispino Antonio , Portaleone Paolo 
Published: April 2011

Abstract
The activity of 2-bromo-α-ergokryptine (bromocriptine) (5 mg kg−1, i.p.) on adenylate cyclase and on phosphodiesterase (PDE I-PDE II) of rat striatum, has been examined both in vitro and in vivo. In vitro and in vivo bromocriptine stimulated adenylate cyclase activity, but reduced the stimulating effect of dopamine on adenylate cyclase activity. Bromocriptine showed a dose-dependent biphasic action on phosphodiesterases in vitro while in vivo it stimulated them. The results obtained proved bromocriptine to have an agonist-antagonist action at striatal dopamine receptor level, with a relevant effect on the cAMP system.
Salicylic acid fails to inhibit generation of thromboxane A2 activity in platelets after in vivo administration to the rat
Authors: Vargaftig Bernardo B 
Published: April 2011

Abstract
Arachidonic acid-induced aggregation of rat platelets and the accompanying generation of thromboxane A2 activity were inhibited by aspirin, whereas 20 times higher doses of salicylic, gentisic and salicyluric acids were inactive. Salicylic acid administered to the rats before aspirin prevented the inhibition of the cyclo-oxygenase-mediated effects of arachidonic acid. These results do not support the hypothesis that the anti-inflammatory activity of salicylic acid is due to inhibition of prostaglandin synthetase (cyclo-oxygenase) by an unknown metabolite and indicate that salicylic acid displays an anti-inflammatory activity independent inhibition of prostaglandin biosynthesis.
Studies on the role of ACTH and of 5-HT in anxiety, using an animal model
Authors: File Sandra E , Vellucci Sandra V 
Published: April 2011

Abstract
The effects of ACTH (5 & 7·5 μg/100 g) were studied using a new animal model of anxiety. ACTH had an anxiogenic effect that was maximal during a 10 min test period starting 3 min after injection. The behavioural effects of ACTH were counteracted by chronic administration of chlordiazepoxide (5 mg kg−1 for 5 days) and by acute administration of ethanol (0·4 g kg−1). These anxiolytic drugs decreased the turnover of 5-HT in the midbrain, hypothalamus and cerebral cortex, whereas ACTH increased 5-HT turnover in the midbrain and hypothalamus. It is therefore proposed that anxiety results from the action of ACTH, possibly on 5-HT pathways in the midbrain and hypothalamus.
Biopharmaceutical properties of liquid and tablet antacids: in vivo studies using the intragastric pH-measurement technique
Authors: Brouwers J R B J , Tytgat G N J 
Published: April 2011

Abstract
Three types of liquid and tablet antacids have been studied in vitro and in vivo: aluminium hydroxide, aluminium hydroxide-magnesium carbonate and hydrotalcite. The effects on gastric pH of antacid suspensions and antacid chewing tablets having identical active ingredients have been studied in 36 volunteers, the sequence of both forms of administration being randomized. Gastric acid secretion was continuously stimulated during the experiment by a pentagastrin infusion. Antacid chewing tablets gave inferior results when compared with the same antacid in liquid. Antacid suspensions are therefore preferred in the treatment of acid-peptic disease.
The diffusion of nandrolone through occluded and non-occluded human skin
Authors: Foreman M I , Clanachan I , Kelly I P 
Published: April 2011

Abstract
Diffusion constants have been measured for nandrolone in human cadaver skin in vitro under conditions which approximate to both the occluded and non-occluded topical therapeutic situation. The results suggest that occlusion affects the diffusion parameters only marginally, if at all, but appears to reduce the ability of the stratum corneum to ‘irreversibly’ bind a fraction of the applied dose. Studies of nandrolone diffusion in freshly excised human epidermis yield similar results to those from measurements on cadaver skin, and it has also been found that epidermal samples excised from non-involved sites of human psoriatic patients behave under these conditions in essentially the same way as normal epidermis.
Circling behaviour in the rat following unilateral injections of p-chlorophenylalanine and ethanol-amine-O-sulphate into the substantia nigra
Authors: Tanner Trevor 
Published: April 2011

Abstract
Circling behaviour following the unilateral intranigral injection of the γ-aminobutyric acid (GABA) transaminase inhibitor ethanolamine-O-sulphate, (EOS), or the tryptophan hydroxylase inhibitor p-chlorophenylalanine (pCPA) was compared, both for spontaneous circling and for circling induced by apomorphine administration. EOS-injected rats exhibited spontaneous contralateral rotation for up to 3 h after such injections. pCPA-injected rats showed only a slight ipsilateral postural asymmetry, both groups of rats elicited ipsilateral rotation upon apomorphine challenge. Increased ipsilateral dopamine release within the corpus striatrum accompanied this response. It is proposed that GABA and 5-HT may be closely related in modifying the nigrostriatal impulse flow.
The synthesis and urinary estimation of N-hydroxyaprobarbitone
Authors: Gilbert John N T , Nelmes Philip T J , Powell John W 
Published: April 2011

Abstract
N-Hydroxyaprobarbitone (I) has been synthesized by oxidation of aprobarbitone, characterized, and a method developed for its estimation in urine. It has shown to be no more than a minor metabolite (&lt;4%) in the human metabolism of aprobarbitone.
Survival of plasmid-containing strains of Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus in phenylmercuric nitrate and thiomersal
Authors: Pinney R J 
Published: April 2011

Abstract
Strains of Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus harbouring plasmids that confer mercury resistance grew in nutrient broth containing concentrations of phenylmercuric nitrate (PMN) that were inhibitory to isogenic plasmid-less strains. Decimal reduction times of P. aeruginosa and S. aureus in aqueous PMN solution were also increased by the presence of plasmids. The viable count of a plasmid-containing P. aeruginosa strain in Davis and Mingioli's minimal medium (DM) containing 10 μg ml−1 PMN fell by approximately 99% after 5 h. The count then remained constant for two weeks, when growth recommenced. This pattern of death followed by growth was also observed with the P. aeruginosa strain in DM + 10 μg ml−1 thiomersal.
Melanocyte-stimulating hormone—mimetic action of the phenothiazines
Authors: Carter R J , Shuster Sam 
Published: April 2011

Abstract
We have compared the melanophore-stimulating action of four phenothiazines, trifluoperazine, perphenazine, chlorpromazine, and prochlorperazine, with α-MSH on the skin of the lizard Anolis carolinensis, using a new rate method of bioassay. The dose-response curves for the phenothiazines were parallel to that of α-MSH, and when given together α-MSH and chlorpromazine were additive. The phenothiazines may therefore stimulate melanosome dispersion in the lizard skin by the same mechanism as α-MSH; a MSH-mimetic action of phenothiazines may similarly explain their pigmentary action in man. The pigmentary potency of the phenothiazines corresponded with their therapeutic potency in man; this is in keeping with a neuro-regulatory role for MSH peptides and suggests a possible therapeutic use for them.
The effect of various topical antibiotic and antibacterial agents on the middle and inner ear of the guinea-pig
Authors: Parker F L , James G W L 
Published: April 2011

Abstract
The topical application of antibiotics and anti-inflammatory agents is used to reduce inflammation of the middle ear mucosa and irradicate infection. Many of the antibiotic and anti-inflammatory preparations so used contain compounds known to be or are potentially ototoxic. Eighteen antibiotic, antibacterial, antifungal and anti-inflammatory compounds and four commonly used solvents were screened for the absence of ototoxicity and inflammation to the middle ear mucosa. All compounds were injected intra-tympanically and sensory hair cell loss recorded graphically. Inflammation of the middle ear mucosa was assessed macroscopically. Of the 18 compounds only three, penicillin, carbenicillin and nystatin were free of hair cell toxicity and inflammatory effects on the middle ear mucosa. Only one of the commonly used solvents was free of side effects.
Inhibitors of gastric lesions in the rat
Authors: Hayden Linda J , Thomas G , West G B 
Published: April 2011

Abstract
The production by stress of gastric lesions in rats was inhibited by metiamide and by mepyramine. Lesions induced by indomethacin treatment were inhibited by mepyramine but not by metiamide. Those induced by aspirin treatment in pylorus-ligated rats were not affected by either antihistamine drug. Oral glutamine inhibited lesion production in all three systems whereas aspirin orally markedly potentiated it. Sodium salicylate inhibited both indomethacin-induced lesions and those produced by aspirin in pylorus-ligated rats. On the other hand, copper salicylate inhibited stress-induced lesions and it, like copper aspirinate, also markedly reduced the extent of lesions produced by aspirin. On the basis of these results, stress-induced lesion production offers a suitable animal model for testing anti-ulcer drugs as it is, like most human gastric ulcers, inhibited by H2-receptor inhibitors like metiamide.
Actions of procaterol (OPC-2009), a new β2-adrenoceptor stimulant, on pulmonary resistance, contractions of the soleus muscle, and cardiovascular system of the anaesthetized cat
Authors: Yamashita Shuji , Takai Masaaki , Yabuuchi Youichi 
Published: April 2011

Abstract
The β-adrenoceptor stimulant actions of procaterol hydrochloride [5-(1-hydroxy-2-iso-propylaminobutyl)-8-hydroxycarbostyril hydrochloride hemihydrate] were compared with those of isoprenaline, orciprenaline and salbutamol on pulmonary resistance, contractions of the soleus muscle, heart rate and diastolic blood pressure in the anaesthetized cat. All four drugs reduced the 5-HT-induced increase in pulmonary resistance, decreased the tension of incomplete tetanic contractions of the soleus muscle and the diastolic blood pressure, and increased the heart rate in a dose-related manner. The duration of the bronchodilator action of procaterol was far longer than that of orciprenaline or salbutamol while isoprenaline had the shortest duration. Procaterol was about 1·5 times more potent, and orciprenaline and salbutamol about 80 and 10 times less potent than isoprenaline in reducing the 5-HT-induced increase in pulmonary resistance and in decreasing the tension of incomplete tetanic contractions of the soleus muscle. Procaterol, orciprenaline and salbutamol were 3·5, 91·9 and 43·9 times less potent than isoprenaline in increasing the heart rate. Procaterol, orciprenaline and salbutamol were 3·4, 130·2 and 12·9 times less potent than isoprenaline in decreasing the diastolic blood pressure. Calculation of selectivity for bronchial vs cardiac β-adrenoceptors indicates that procaterol and salbutamol have a similar degree of selectivity for β2-adrenoceptors mediating the bronchodilation, and that orciprenaline was an essentially unselective stimulant. Furthermore, the results support the suggestion that at present it is not possible to separate the bronchodilating and tremor-enhancing properties of β-adrenoceptor stimulants.
Tryptamine-induced drug effects insensitive to serotoninergic antagonists: evidence of specific tryptaminergic receptor stimulation?
Authors: Quock Raymond M , Weick Barton G 
Published: April 2011

Abstract
The drug effects of tryptamine and 5-hydroxytryptophan (5-HTP) in the rabbit were compared following monoamine oxidase inhibition and various drug pretreatments. Both agents evoked hyperthermia and behavioural excitation; tryptamine but not 5-HTP also produced forepaw clonic activity. Serotoninergic receptor blockers abolished the effects of 5-HTP but only weakly influenced tryptamine responses. Both tryptamine and 5-HTP effects were potentiated by fluoxetine. Methergoline, a putative tryptaminergic receptor blocker, antagonized tryptamine-induced hyperthermia and forepaw clonus but did not influence 5-HTP responses. It is postulated that while 5-HTP produces its effects through a serotoninergic mechanism, some of the responses to tryptamine result from activation of a specific tryptamine-sensitive mechanism.
Some pharmacological actions of acetylsecohemicholinium
Authors: Hemsworth B A , Cholakis J M 
Published: April 2011

Abstract
The effects of the acetylated derivative of HC-3 (acetylsecohemicholinium; AcHC-3) have been studied at cholinergic nerve terminals and compared with the effects of the parent compound. AcHC-3 blocked neuromuscular transmission in nerve-muscle preparations; it was shown to be less effective than HC-3 in producing a pre-junctional block in the rat diaphragm but was more effective than HC-3 in eliciting a post-junctional blocking effect in the chick biventer muscle. On the frog rectus abdominis muscle AcHC-3 caused a substantial potentiation of the contractures elicited by acetylcholine but did not by itself cause a contracture of the muscle. AcHC-3 inhibited the synthesis of acetylcholine by cholinergic nerve ending particles and inhibited the uptake of [14C]choline into brain synaptosomal fractions to a similar extent to HC-3. AcHC-3 was shown to be a substrate for cholinesterase enzymes although the rate of hydrolysis was much less than the rate of hydrolysis of acetylcholine. It is concluded that AcHC-3 is effective in inhibiting cholinergic transmission and this acticn is exerted by the open chain (seco) compound and is not due to the hydrolysis of the AcHC-3 by cholinesterases to form the active HC-3 molecule.
Interaction of cortisol-21-palmitate with liposomes examined by differential scanning calorimetry
Authors: Fildes F J T , Oliver J E 
Published: April 2011

Abstract
Liposomes have been suggested as carriers for corticosteroids in the local treatment of arthritis by intra-articular injection. The long chain 21-esters of Cortisol such as the palmitate or octanoate are taken up and retained by liposomes in higher concentration than cortisol itself. Differential scanning calorimetry has been used to show that the cortisol ester is anchored in the liposome phospholipid bilayer by the acyl side chain. In addition, the limiting concentration of cortisol-21-palmitate which can be incorporated into dipalmitoyl phosphatidylcholine liposomes has been measured by observing changes in the DSC spectrum at different steroid concentrations. Steroid in excess of this concentration limit forms a separate phase which can be identified by nuclear magnetic resonance. For optimum effect, the treatment of arthritis with liposomes must be carried out with liposomes containing steroid below the limiting concentration.
In vitro and in vivo defoaming action of three antacid preparations
Authors: Stead J A , Wilkins R A , Ashford J J 
Published: April 2011

Abstract
The defoaming activity of three tablet antacids (hydrotalcite, hydrotalcite/dimethicone and aluminium hydroxide/dimethicone) powdered to 60 mesh was measured in vitro using a new static/dynamic technique. Their antacid actions and that of aluminium hydroxide gel B.P.C. were also measured using a modified Fuch's test. Combination of dimethicone with hydrotalcite conferred good defoaming activity with little effect on pH profile whilst combination of aluminium hydroxide with dimethicone markedly altered both. Additionally, the defoaming actions of the three commercial antacids were assessed in vivo. Radiographs were taken after administration of antacid, a foaming mixture and a normal barium meal. The radiographs were then ranked blind by 5 radiologists. The rankings assigned the significantly greatest (Mann-Whitney U-test) defoaming effect to the hydrotalcite/dimethicone combination, there being no difference between the other two preparations. The in vitro results were thus confirmed.
Correlation of physicochemical properties with absorption and metabolism of some tricyclic drugs
Authors: Gescher A , Po A Li Wan 
Published: April 2011

Abstract
Octanol and dodecane partition coefficients, surface activity and adsorbability to activated charcoal were determined for six tricyclic psychotropic drugs with N-dimethylalkyl side chains. Surface activity correlated well with the partition coefficients, and all drugs obeyed the Langmuir adsorption isotherm. A correlation between the reciprocal of the death time of gold fish exposed to drugs and partition coefficients was observed. The extent to which the drugs were N-demethylated as measured by formaldehyde formed in rat liver homogenate incubations correlated with their adsorbability to activated charcoal but not with their ability to inhibit aniline-p-hydroxylase, nor was there a linear correspondence between N-demethylation and drug lipophilicity as indicated by partition coefficients or surface activity.