bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cardiovascular responses in spontaneously hypertensive rats with acute renal failure
Authors: Yates M S , Bowmer C J , Brown G M 
Published: April 2011

Abstract
Cardiovascular status and reactivity have been investigated in spontaneously hypertensive rats (SHR) with glycerol-induced acute renal failure. SHR with acute renal failure had significantly lower mean arterial blood pressures and heart rates. The pressor responses to noradrenaline and the chronotropic responses to right cervical sympathetic and vagal nerve stimulation were diminished in uraemic SHR compared to control SHR. The cardiovascular depression observed in SHR with acute renal failure was similar to that previously noted in normotensive rats with acute renal impairment.
Inhibition of prostaglandin synthesis in rabbit kidney medulla slices by antioxidants
Authors: Fujimoto Yohko , Tanioka Hidetoshi , Toibana Eiko , Yamamoto Taku , Fujita Tadashi 
Published: April 2011

Abstract
The inhibitory effects of NN’-diphenyl-p-phenylenediamine (DPPD), sodium diethyldithiocarbamate (SDDC) and 2,6-di-t-butylphenol (DTBP) on the generation of medullary prostaglandin E have been compared. DPPD (1 μm) and SDDC (1 mm) failed to inhibit arachidonic acid-induced stimulation of prostaglandin E synthesis, while DTBP (1 mm) inhibited it. This suggests that DPPD and SDDC inhibit prostaglandin formation by affecting a phospholipase pathway, and the inhibition of prostaglandin generation by DTBP occurs at the cyclooxygenase step.
Effects of lipoxygenase inhibitors in arachidonate-induced sudden death
Authors: Roth David M , Feduska Richard , Lefer Allan M , Smith J Bryan 
Published: April 2011

Abstract
Both BW 755c, a cyclo-oxygenase and lipoxygenase inhibitor, and nordihydroguaiaretic acid (NDGA), a selective lipoxygenase inhibitor, were tested for their protection against arachidonate-induced sudden death in rabbits. 100% survival was seen with BW 755c (1 mg kg−1), while NDGA showed 0 and 17% survival (2 mg kg−1 and 4 mg kg−1). BW 755c prevented 12-fold increases in plasma thromboxane B2 concentrations and the formation of pulmonary artery thrombi normally seen with arachidonate-induced sudden death, while NDGA showed no such protective effect. Radioimmunoassay of rabbit plasma for leukotrienes (LTC4, LTD4 and LTE4) indicated that they do not accumulate in blood in the model and BW 755c had no effect, suggesting that the deleterious effects seen are caused by cyclo-oxygenase pathway metabolites such as thromboxane A2, but not by lipoxygenase pathway products such as leukotrienes.
Contractile effect of 1-O-hexadecyl-2-O-acetyl-sn-glycero-3-phosphocholine on strips of isolated rat intestine
Authors: Tokumura A , Fukuzawa K , Tsukatani H 
Published: April 2011

Abstract
The contractile effects of AGEPC were examined on various regions of rat isolated intestine. The duodenum, jejunum and ileum showed only the tonic component of contraction to AGEPC at the low dose (&lt;10−9 m) but at the high dose (10−7 m) biphasic contractions were induced, consisting of a phasic followed by a tonic component. In the colon, however, the AGEPC-induced maximum contraction was comparable in magnitude to that produced by acetylcholine; also the contraction profile was different from that elicited from the other regions of the intestine. Low doses of AGEPC caused a slow, sustained contraction and at high doses phasic and tonic components were not dissociated.
Influence of smoking on serum protein composition and the protein binding of drugs
Authors: Benedek I H , Blouin R A , McNamara P J 
Published: April 2011

Abstract
The influence of smoking on α1-acid glycoprotein (α1-AGP) and serum albumin concentrations and the protein binding of phenytoin and propranolol in healthy volunteers was investigated. α1-AGP concentrations were found to be statistically different (P &lt; 0·05) in the smokers (mean = 84·3 mg dl−1) versus non-smokers (mean = 62·8 mg dl−1). There was a trend for lower serum albumin concentrations and lower fraction unbound of propranolol in the smokers. Smoking did not affect the protein binding of phenytoin.
The effect of punch velocity on the compaction of a variety of materials
Authors: Roberts R J , Rowe R C 
Published: April 2011

Abstract
The effect of punch velocity over the range 0 033–400 mms−1 on the compaction of a variety of materials has been studied using constants derived from the Heckel equation as criteria to describe their behaviour. For materials known to deform plastically, e.g. maize starch and polymeric materials, there was an increase in the yield pressure with punch velocity attributable to a change either from ductile to brittle behaviour or a reduction in the amount of plastic deformation due to the time dependent nature of plastic flow. For materials known to consolidate by fragmentation, e.g. magnesium and calcium carbonates, there was no change in yield pressure with increasing punch velocity. The data has been analysed in terms of the strain rate sensitivity of the materials calculated from their yield pressure at low and high punch velocities.
The effect of polycations on the activity of pepsin
Authors: Lawton J B , Mekras C I 
Published: April 2011

Abstract
A study has been made of the interaction of selected polycations with pepsin A (E.C. 3.4.23.1). Protamine, polybrene, spermine, spermidine and poly(L-lysine) all acted as inhibitors of the enzyme at low concentrations, but at higher concentrations of the polycations the inhibition was less pronounced. A more detailed study of the anomalous inhibition was made using protamine, polybrene and poly(L-lysine) and it was shown experimentally that, when used by themselves, each of these polycations acted as a weak proteolytic catalyst. The order of catalytic effectiveness was: protamine &gt; polybrene » poly(L-lysine). Thus, it is now possible to explain why the observed inhibition of pepsin decreases when the concentration of the inhibiting polycation is increased.
The active principles of the branchlet and hook of Uncaria sinensis Oliv. examined with a 5-hydroxytryptamine receptor binding assay
Authors: Kanatani Hirotoshi , Kohda Hiroshi , Yamasaki Kazuo , Hotta Izumi , Nakata Yoshihiro , Segawa Tomio , Yamanaka Etsuji , Aimi Norio , Sakai Shin'ichiro 
Published: April 2011

Abstract
Of the alkaloids obtained from Uncaria sinensis Oliv., geissoschizine methyl ether, corynantheine and dihydrocorynantheine decreased specific [3H]5-HT binding to membrane preparations from rat brain and from in-vitro experiments on guinea-pig ileum, these alkaloids were found to be partial agonists for 5-HT receptors. Therefore, they might be useful in the treatment of diseases resulting from disorders of 5-HT metabolism.
Peripheral cardiovascular α- and β-adrenergic effects of some hypotensive and bradycardic arylalkyl imidazole derivatives in the rat
Authors: Savola J-M , Puurunen J , Ruskoaho H , Kärki N T 
Published: April 2011

Abstract
In pithed rats, a series of four alkyl bridge analogues of 4(5)-substituted arylalkyl imidazole induced α-adrenoceptor-mediated vasoconstriction and inhibition of electrically stimulated tachycardia. These effects were induced in the order of potency clonidine = MPV 207 &gt; MPV 295 &gt; MPV 304 &gt; MPV 390, correlating with the length of the alkyl bridge between the phenyl and imidazole moieties. The peripheral postsynaptic actions of MPV 207 and MPV 304 were attenuated by prazosin (0.1 mg kg−1 i.v.) and yohimbine (1 mg kg−1 i.v.). The pressor responses induced by MPV 295 were antagonized only by yohimbine (0.3 and 1 mg kg−1 i.v.). The peripheral sympathoinhibitory action of these compounds was antagonized by yohimbine (1 mg kg−1 i.v.). In spontaneously beating rat atria, the MPV compounds showed neither agonistic nor antagonistic activity at cardiac postsynaptic α- and β-adrenoceptors. The results indicate that the hypotensive and bradycardic MPV compounds are agonists at peripheral cardiovascular α-adrenoceptors. The extension of the alkyl bridge between the phenyl and imidazole moieties reduces their activity at α-adrenoceptors. Finally, MPV 295 seems to be a selective agonist of peripheral α2-adrenoceptors in the cardiovascular system of the pithed rat.
Solute conformation of enkephalin-like pentapeptides in deuterated dimethylsulphoxide
Authors: Casy A F 
Published: April 2011

Abstract
NMR evidence of the temperature dependence of NH resonances and magnitudes of α-CH-NH couplings is advanced in support of preferred β-bend conformations for five enkephalin-like pentapeptides as solutes in DMSO-d6. The relevance of these and related conformational studies to the interactions of peptides of the enkephalin class with opioid receptors is questioned.
Comparative effects of sodium azide and aminophylline on the rat isolated uterus during muscle activation
Authors: Milovanović S R , Varagić V M 
Published: April 2011

Abstract
Sodium azide is a strong inhibitor of the tonic component of contraction produced by oxytocin, whereas aminophylline produces almost equal inhibition of all types of activation of the isolated rat uterus. Both substances inhibited the spontaneous rhythmic activity of the uterus. The effect of sodium azide is easily reversed by calcium. The results are taken to indicate a complex relation between calcium and substances which stimulate metabolism either of cGMP (sodium ***azide) or cAMP (aminophylline) in producing relaxation of the isolated rat uterus.
Gastrointestinal neurotensin receptors: lack of modulation by thyrotropin releasing hormone
Authors: Donoso M Veronica , Huidobro-Toro J Pablo 
Published: April 2011

Abstract
To examine whether thyrotropin releasing hormone (TRH) antagonized gastrointestinal neurotensin receptors in isolated segments of the rat fundus, duodenum and ileum, tissues were superfused, mounted and the isometric tension recorded. Picomoles of neurotensin caused concentration-dependent contractions of the fundus and relaxation of the smooth muscles of the small intestine. Preincubation with 1–10 μm TRH failed to antagonize the activity of neurotensin but potentiated neurotensin-induced relaxation of the ileum. Pretreatment of the tissues with 0.6 μm of neuropeptide fragment 1–11, also failed to block the neurotensin-induced effects but produced a significant potentiation of the relaxant action of neurotensin.
Dose-dependent absorption of disodium etidronate
Authors: Gural Richard P , Chungi Vinod S , Shrewsbury Robert P , Dittert Lewis W 
Published: April 2011

Abstract
The gastrointestinal absorption of disodium etidronate (as [14C]disodium etidronate) was investigated in the rat proximal jejunum in-situ. Studies using various initial concentrations of the drug suggested that etidronate absorption occurred by passive diffusion at initial concentrations below 0.08 M. At initial concentrations above 0.08 M, the rate of absorption was significantly greater than would be expected if passive diffusion was the only mechanism responsible for absorption. Etidronate absorption is not mediated by the carrier mechanism responsible for phosphate ion absorption.
The effect of the surface free energy of pharmaceutical tablets on liquid penetration
Authors: De Lourdes Costa Maria , Baszkin Adam 
Published: April 2011

Abstract
The surface free energies (γsv) of the integral and partial tablet formulations of an antiarrhythmic drug—cibenzoline succinate, have been assessed by contact angle measurements using high-viscosity polyols and Neumann's equation of state. Independent measurements of penetration for these liquids into the tablets yielded pore size values through the use of the Washburn equation. The role of different constituents of the formulations are analysed in terms of their influence upon the free surface energy of the tablets and penetration rates. The relation between (γsv) and penetration rates yields for a series of liquids two threshold values: (γsv)s ‘start’ and (γsv)r ‘rapid’, which define respectively the beginning of the measurable penetration and the rapid penetration.
Absorption characteristics of the lipophilic prodrug of mitomycin C from injected liposomes or an emulsion
Authors: Sasaki Hitoshi , Kakutani Toshiyuki , Hashida Mitsuru , Sezaki Hitoshi 
Published: April 2011

Abstract
Mitomycin C (MMC) is amphiphilic and so cannot be incorporated into lipoidal delivery systems. To develop a lipoidal delivery system, its prodrug, nonyloxycarbonyl MMC, was formulated in liposomes and in o/w emulsions and the usefulness of these formulations was evaluated. After injection into the rat thigh muscle, MMC was rapidly absorbed regardless of the dosage form. However, the prodrug was retained at the injection site for considerably longer when formulated in a lipid dispersion system. The accumulation of MMC at regional lymph nodes was also investigated and whereas free MMC arrived at and disappeared from the lymph nodes almost immediately after injection, the prodrug arrived at an early stage and its concentration decreased only gradually, remaining fairly high 2 h after injection. Liposomal lipids appeared to accumulate at the lymph nodes to a greater degree than o/w emulsions. It is suggested that the combination of lipidic carrier devices with lipophilic prodrugs may be a useful adjunct to cancer chemotherapy.
Effect of age on the hepatic clearance of propranolol in rats
Authors: Iwamoto Kikuo , Watanabe Jun , Araki Kaoru , Deguchi Naoko , Sugiyama Hisako 
Published: April 2011

Abstract
The effect of age on hepatic clearance of propranolol was investigated in male Wistar rats (3 to 104 weeks old). Pharmacokinetic analysis of the plasma propranolol data obtained after i.v. dosage (1.0 mg kg−1) indicated that both the elimination rate constant and the volume of distribution decreased with age between weeks 5 and 11, after when the distribution volume remained almost constant. The elimination rate constant was reduced consistently with age after 15 weeks. Total body clearance of the drug was reduced extensively with age between weeks 5 and 11 (94 to 43 ml min−1 kg−1) and decreased gradually thereafter. The plasma free fraction of propranolol also decreased with age, falling from more than 20% in 3 to 5 weeks-old rats to about 10% in rats of 52 to 104 weeks. In immature rats the renal clearance was approximately 5 to 12% of the total body clearance. Intrinsic hepatic clearance for unbound propranolol also decreased with age between weeks 7 and 24. As expected from the evidence that propranolol has a high extraction ratio, the extent of its hepatic clearance was significantly dependent on the liver blood flow. These data suggest that the age-dependent decrease in hepatic clearance of propranolol is largely due to a reduction of the elimination rate that might be accompanied by the age-dependent decrease in liver blood flow.
Vascular reactivity in experimental acute renal failure
Authors: Yates M S , Askey Elizabeth A , Wilmot Susan E , Bowmer C J 
Published: April 2011

Abstract
Vascular reactivity in-vivo and in-vitro was examined in rats with acute renal failure produced by bilateral nephrectomy or intramuscular glycerol injection. Bilaterally nephrectomized rats displayed enhanced pressor responses to noradrenaline and angiotensin. However, the contractile responses to noradrenaline, angiotensin and potassium chloride of aortic rings and portal vein segments from nephrectomized rats were not significantly different from the responses obtained in vessels from sham-operated controls. Rats with glycerol-induced ARF which were pretreated with indomethacin had significantly lower pressor responses to noradrenaline and angiotensin than similarly treated control animals. Aortic rings from glycerol-injected rats produced significantly smaller contractions to noradrenaline than preparations from controls. This difference was not abolished by incubation of vessels with indomethacin. The findings suggest that the absence of kidneys or the presence of damaged renal tissue and not uraemia itself have pronounced but opposite effects on vascular reactivity. The depression of vascular reactivity in glycerol-induced ARF does not appear to be a result of increased production of prostaglandins.
Tensile anisotropy of some pigmented tablet film coating systems
Authors: Okhamafe Augustine O , York Peter 
Published: April 2011

Abstract
The tensile properties of representative tablet film coating systems, containing hydroxypropyl methylcellulose alone and in combination with either polyvinyl alcohol, polyethylene glycol 400 and polyethylene glycol 1000 and pigmented with either talc or titanium dioxide, have been investigated. Tensile anisotropy was observed between film samples cut parallel to, and perpendicular to, the direction of rotation of the casting substrate and factors accounting for this phenomenon are presented.
Penetration of the human nail plate: the effects of vehicle pH on the permeation of miconazole
Authors: Walters Kenneth A , Flynn Gordon L , Marvel John R 
Published: April 2011

Abstract
In order to assess the relative permeability of the nail plate to ionized and unionized drugs the permeation of miconazole at varying pH has been followed as a function of time. The pH was adjusted from 3.1 to 8.2 to obtain between 5 and 100% dissociation of the drug. No significant difference in the rate of permeation was demonstrated. The data suggests that the ionic form of miconazole dissolves as easily in the nail plate as the free base and, therefore, topical bioavailability can be enhanced by decreasing the formulation pH thereby increasing drug solubility.
Some actions of sodium nitroprusside and glyceryl trinitrate on guinea-pig isolated trachealis muscle
Authors: Kishen R , Pleuvry B J 
Published: April 2011

Abstract
The smooth muscle relaxant actions of sodium nitroprusside and glyceryl trinitrate have been compared to those of aminophylline and isoprenaline on isolated guinea pig trachealis muscle. Ethacrynic acid (0.25 times 10−4 M), an alkylator of sulphydryl groups, interacted differently with the four agents. In the presence of ethacrynic acid the concentration response curve of the muscle preparation to sodium nitroprusside and glyceryl trinitrate was shifted to the higher concentration ranges and the maximum response was severely reduced. The concentration response curve for isoprenaline was shifted to the higher concentration ranges with no change in the maximum response and the response to aminophvlline was unchanged. These results argue against common intermediate sites of action involving sulphydryl groups of the four agents in guinea-pig trachealis.
Prolongation of thiopentone-induced sleep by trazodone and its metabolite, m-chlorophenylpiperazine
Authors: Adamus Anna , Sansone Mario , Melzacka Miroslawa , Vetulani Jerzy 
Published: April 2011

Abstract
Trazodone and its metabolite, m-chlorophenylpiperazine (CPP) prolonged significantly thiopentone-induced sleep in mice. Neither trazodone, nor CPP changed the cerebral concentrations of thiopentone. As cyproheptadine by itself did not affect thiopentone sleep and did not antagonize the effect of CPP, the effect of trazodone and CPP seems to be independent of their respective 5-HT-antagonistic and 5-HT-agonistic properties.
Evidence for the dissociation of morphine analgesia, tolerance and dependence
Authors: Kaneto Hiroshi , Yamazaki Akira , Kihara Tsuyoshi 
Published: April 2011

Abstract
A single large dose of morphine produced profound analgesia accompanied by the development of tolerance and physical dependence. The tolerance developed acutely within 24 h and was further intensified, reaching a peak on the 5th day, then gradually disappeared. Partial or complete masking of morphine analgesia by naloxone inhibited the development of the acute, but could not prevent the development of the delayed, tolerance. These results suggest there are two kinds of tolerance and that the analgesic effect is separate from tolerance. Similarly, treatment with morphine produced physical dependence which was precipitated by naloxone, Unlike tolerance, dependence did not develop when morphine analgesia was completely masked by naloxone. The findings provide for the dissociation or morphine analgesia, tolerance and dependence.
Lymphatic transport of sodium cefoxitin in the presence of sodium 5-methoxysalicylate after injection into rat rectal connective tissue, femoral muscle and femoral vein
Authors: Nishihata Toshiaki , Kim Suni , Kamada Akira , Frederick Gregory , Dillsaver Margaret , Higuchi Takeru 
Published: April 2011

Abstract
Lymphatic uptake of sodium cefoxitin after injection into rectal connective tissue was greater than after injection into the femoral muscle of rats. Coadministration with sodium 5-methoxysalicylate enhanced lymphatic drug uptake at both sites. This enhancement may be an indirect result of 5-methoxysalicylate's suppression of vascular permeation of the cefoxitin. An adjuvant-induced increase in lymphatic fluid flow may also be partially involved in the enhancement of cefoxitin lymphatic transport.
Characterization of enhanced intestinal permeability; electrophysiological study on the effects of diclofenac and ethylenediaminetetraacetic acid
Authors: Yamashita Shinji , Saitoh Hidetaka , Nakanishi Kunio , Masada Mikio , Nadai Tanekazu , Kimura Toshikoro 
Published: April 2011

Abstract
The mechanism of the enhancing effects of diclofenac sodium and disodium ethylenediaminetetraacetate (EDTA) on intestinal permeability to sulphanilic acid were investigated in the rat isolated jejunum by an electrophysiological technique. The results suggested that diclofenac sodium increased the mucosal-to-serosal flux rate of sulphanilic acid by enhancing both transcellular and paracellular permeabilities while the effect of EDTA was located only in the paracellular pathway.
Analysis of particulate contamination in ampoules using a light blockage particle analyser
Authors: Alexander D M , Veltman A M 
Published: April 2011

Abstract
A method of opening ampoules without introducing particles has been developed and the level of particulate contamination in a number of ampoule solutions using a light blockage particle analyser (HIAC) has been determined. Low levels of contamination were found and a method of setting limits of particulate contamination in ampoules is suggested.
In-vitro and in-vivo protection of acetylcholinesterase by eseroline against inactivation by diisopropyl fluorophosphate and carbamates
Authors: Galli A , Aiello P Malmberg , Renzi G , Bartolini A 
Published: April 2011

Abstract
The protective action of eseroline—(3aS, 8aR)-l,2,3,3a,8,8a-hexahydro-l,3a,8-rimethyl-pyrrolo[2,3-b]indol-5-ol—salicylate against (DFP) diisopropyl fluorophosphate and carbamate poisoning of cholinesterases (ChEs) has been examined in-vitro with human erythrocytes and purified preparations of electric eel acetylcholinesterase (AChE) and of horse serum butyrylcholinesterase (BuChE), and in-vivo using mice. Eseroline afforded 50% protection (ED 50) of erythrocyte AChE against inactivation by 1 μM DFP, physostigmine or neostigmine, at concentrations of 4.3, 22 and 23.5 μM, respectively, while for eel AChE protection against 10 and 30 μM DFP, 0.3 and 1 μM physostigmine and 1 μ m neostigmine the eseroline ED 50 values were 0.3, 0.4. 0.7, 1.9 and 5.6 μM, respectively. On the other hand, up to 0.3 mM eseroline did not appreciably affect the inhibitory action of the same drugs on horse serum BuChE. Eseroline concentrations in the range 0.1-1 mM were able to reactivate 20-42% of erythrocyte AChE previously inhibited by 100 μM physostigmine, but failed to reactivate the DFP (10 μM)-pretreated enzyme to any extent. Finally, eseroline salicylate injected into mice (10 mg kg−1 s.c.) protected an average of 82 and 26% of the animals against lethal doses of DFP (7mg kg−1 s.c.) and physostigmine sulphate (1 mg kg−1 i.p.) respectively, which were administered 15 min later. These results indicate that the protective activity of eseroline correlates well with its own anti-ChE profile, and that the effectiveness of the protection depends largely on the rate of AChE inhibition by the agents used to inactivate the enzyme.