Pharmacological modulation of neurogenic inflammation.

A neurogenic inflammation was induced by electrical stimulation of the exposed saphenous or sciatic nerve of male rats. The increase in paw weight of the stimulated leg was used as parameter for degree of inflammation. The content of substance P decreased significantly in the skin supplied by the antidromic stimulated nerves. Substances were tested whose effectivity in neurogenic inflammation is as yet unknown. Inhibition of the angiotensin converting enzyme by the inhibitor captopril did not yield an indirect reference for a causative role of substance P in neurogenic inflammation. The activity of catecholamines refers to the possible importance of blood vessel and/or cyclic nucleotide level alteration in this special type of inflammation.

Reactivity of resistance blood vessels ex vivo after administration of toxic chemicals to laboratory animals: arteriolotoxicity.

Three vasotoxic metals (arsenic, lead, cadmium) were investigated for their arteriolotoxicity in rats. A perfused hindleg preparation from control and treated animals was used to determine the vasoreactivity to norepinephrine. After 2 and 4 weeks of treatment with arsenic trioxide (15 mg/kg p.o.) and after 4 weeks of treatment with lead acetate (100 mg/kg p.o.), there was a significant reduction in vasoreactivity (10 20%) expressed as the maximum increase in perfusion pressure (EAmax). A single dose of cadmium chloride (1 mg/kg i.p.) caused a non-significant reduction of 12% in EAmax. We conclude that this method is suitable for detecting arteriolotoxic effects of chemicals in small laboratory animals.

Problems and results in testing the possible mode of anti-inflammatory glucocorticoid action in carrageenin rat paw oedema: advantages of local substance injection.

The anti-inflammatory effect of dexamethasone in carrageenin rat paw oedema was significantly reduced or abolished by local injection of 0.5-2.5 mg of the antiglucocorticoid progesterone, or of 5 micrograms cycloheximide, or of 2.5 micrograms actinomycin D, into the oedematous area. The results point to indirect dexamethasone action via receptor occupation and de novo protein synthesis, but this view could not be undoubtedly confirmed by systemic administration of essentially higher doses of the substances. The advantages of local low dose antagonist administration versus systemic injection of higher doses are mainly the production of effective tissue levels, as well as avoidance of toxic and other side-effects.

[Automatic, electronic determination of resting time in small laboratory animals and the effect of psychopharmaceuticals]. / Automatisierte, elektronische Bestimmung der Ruhezeit am kleinen Labortier und Einfluss von Psychopharmaka.

The free movements of a small laboratory animal on the bottom of a cage, containing capacitive sensors, are measured as electrical signals which are then amplified, classified in a classification device and counted. With reference to the class of the highest sensitivity and by the choice of appropriate device parameters, signals are only counted during the time in which animal movements are below a level defined as rest. By this, the resting time can be determined which expresses the time in which animals are in the defined rest during the whole test time. The ED50, namely the doses after which the resting time increases by 50% during the first 10 min of the exploration phase of mice has been determined of diazepam, chlordiazepoxide, haloperidol, droperidol, fluphenazine, butaperazine, 7-fluorobutaperazine, and chlorpromazine and it was compared with the ED 50 determined in the contact bottom plates motimeter according to Knoll et al. in mice and in the catalepsy test according to Wirth et al. in rats. respectively. The method of resting time determination has proved as to be striking more sensitive (5- to 10-fold) than the other methods.

[Antiphlogistic effectiveness of combinations of inhibitors of phospholipase A2, cyclooxygenase and lipoxygenases of the arachidonic acid cascade]. / Antiphlogistische Wirksamkeit von Kombinationen von Hemmern der Phospholipase A2, Cyclooxygenase und Lipoxygenasen der Arachidonsäurekaskade.

Combinations of inhibitors of phospholipase A2, cyclooxygenase and lipoxygenase as the key enzymes of the arachidonic acid cascade were investigated with respect to their anti-inflammatory effectivity in the carrageenin paw edema and adjuvant arthritis of rats. Combinations of indometacin with butylhydroxytoluene, quinacrine, lidocaine or/and procaine gave additive or overadditive effects in the carrageenin edema. Addition of ascorbic acid decreased the effectivity. Similar results as with indometacin were obtained with dexamethasone. The "steroid saving effect" of the combination of a glucocorticoid with a non-steroidal anti-inflammatory analgesic was confirmed in the carrageenin edema. However, it could not be found in the adjuvant arthritic rat with dexamethasone and declofenac-Na. The fitness of the models is discussed.

[The biotransformation and toxicity of xenobiotics in the chick embryo. 1. The embryonated hen's egg as an in vivo model and sodium salicylate as substrate]. / Biotransformation und Toxizität von Xenobiotica im Kükenembryo. 1. Mitteilung: Embryoniertes Hühnerei als in-vivo-Modell und Natriumsalicylat als Substrat.

After application of sodium salicylate (1) on d 6 of incubation into the yolk sac of the embryonated hen's egg (Gallus domesticus) 3 compounds were detected in the allantois fluid (AF) dependent on embryo age. Compounds were isolated and identified (M.p., MS, TLC, HPLC) as salicylic acid (1a), o-pyrocatechuic acid (2,3-dihydroxy benzoic acid; 2) and gentisic acid (2,5-dihydroxy benzoic acid; 3), respectively. 1a, 2 and 3 are eliminated from chick embryo in both the free and the glucuronidated form. The toxicity of 1 which was inoculated on d 6 of incubation increased between d 10 and 18 of the embryo age (LD50 318 and 281 mg X kg-1 egg weight, respectively, parallel to the rise of building and excretion of dihydroxy benzoic acid metabolites (increase from 0 to 78.5% of total metabolites).

[Movement profile analysis--automatic registration and evaluation of the movement patterns of small animals]. / Bewegungsprofilanalyse--automatische Registrierung und Auswertung des Bewegungsmusters kleiner Versuchstiere.

A method is described, in which small laboratory animals are freely moving in the field of analogous capacitive sensors. The electrical signals induced by animal movements which, according to amplitude and polarity, contain informations on intensity and direction of movements are conveyed to a classification device and classified according to well-defined classes. By measuring during a fixed time (e.g. 10 min) or for a previously determined number of signals (e.g. 2000) a distribution of class frequencies, the movement profile, is obtained. Parameters of movement profile of mice in the orientation phase and factors of influence are reported on. The method allows the continuously automatic registration of movement profiles.

[The neuroleptic efficiency of some butyrophenone and fluorinated phenothiazine derivatives (author's transl)]. / Neuroleptische Wirksamkeit einiger Butyrophenon- und fluorierter Phenothiazinderivate.

The action of butaperazine was diminished and simultaneously prolonged by fluorination in the position 3 or 7 as evidenced by a number of tests (prolongation of the resting time, catalepsy, apomorphine and dexphenmetrazine antagonism, conditioned escape reflex, aggressivity, algesimetry) on the rat and the mouse. The same seems to apply, in principle, to promazine and prochlorperazine. In contrast, the action of 7-fluorperphenazine and its esters with adamantanic acid and decanoic acid was markedly increased, but not prolonged, as demonstrated by a test (conditioned escape reflex) on the rat. The potency of fluphenazine is reached, but not its duration of action. This finding still needs confirmation by other tests. The duration of action of the butyrylphenazine esters was scarcely longer than that of butyrylphenazine. Considerable irritation has been seen at the site of injection. The esters of long-chained fatty acids and fluperidol and trifluperidol seem to be more potent than the parent substances. There is obviously no prolongation of the duration of action. The activity of the haloperidol oxime ethers (and probably of the esters, too) is weak as compared to that of haloperidol. The duration of action is not prolonged.

[Bioavailability of drugs--concepts and problems]. / Bioverfügbarkeit von Arzneimitteln--Begriffe und Probleme.

The development of the concept of bioavailability is dealt with on the basis of definitions published in the literature. In this connexion, the often extent divergency between the definition and the determination of bioavailability in practice is indicated. Furthermore, the bioavailability is differentiated from the amount of absorption. With regard to the inclusion of the levels of in vitro liberation, liberation in the body and absorption achieved, the frequently stated use of one and the same term for different contents gives rise to a disentanglement of the terms. Perspectively, the inclusion of animal experimentation in pharmacokinetic-biopharmaceutical investigations is insisted on.

[The effect of drugs on electronically determined movement profile (movement profile analysis)]. / Beeinflussung des elektronisch erfassten Bewegungsprofils von Mäusen durch Pharmaka (Bewegungsprofilanalyse).

In the movement profile analysis, movements of small laboratory animals, according to both intensity and direction (amplitude and polarity), are electronically measured by means of capacitive sensors. The electrical signals are amplified, classified into 13 classes in a classification device and depicted as frequency distribution. The obtained distribution corresponds to a Gaussian distribution if normal control mice are used (normal movement profile, MP). The normal MP is characteristically changed by drugs. By centrally depressing drugs (droperidol, chlorpromazine, diazepam, medazepam) distribution classes of weak movements are dose-dependently increased while classes of strong movements are decreased. Stimulating drugs (dexphenmetrazine, methamphetamine, caffeine) gave opposite changes of the MP. A certain time after a stimulating drug the change of the MP can turn to the MP of depressing drugs obviously as the result of exhaustion of the animal. After low doses of echinoramine I a MP with the characteristics of a depressing drug was found, after high doses the MP was that of a stimulating drug, perhaps as the result of subtoxic effects. After apomorphine (1, 5, and 10 mg/kg) no clear dose-dependence could be found. The movement profile analysis can be useful in the specified analysis of movements-influencing drugs.

[The testing of long-term antirheumatics in animals]. / Zur Testung von Basisantirheumatica am Tier.

There is no group proof of long acting antirheumatics (LAA) in laboratory animal models, and it is not to be expected without an identical rheumatoid arthritis model in animals and with regard to the heterogeneity of LAA. However, LAA are to be detected according to D-penicillamine-like, levamisol-like etc. actions, which can be disclosed in the adjuvant arthritis as well as in the B. pertussis-vaccine pleuritis in rats the latter model best by including parameters of inflammatory exudate cells. Modification of the models or of model parameters (BCG-sensibilization, PPD reaction, vasoreactivity, RNA content of exudate cells, SH groups, copper zinc) are hardly advantageous, contrarily to dosage. Other models, among them paw edemas, do not permit sufficient testing of LAA, even not the methyl-albumin mice paw edema. There is no problem of pharmacologically separating LAA actions from nonsteroidal or steroidal antiphlogistics actions.

[An ex-vivo technic for the pharmacologic evaluation of potential antiphlogistics by ex-vivo determination of the rate of malondialdehyde (MDA) formation using rat platelets]. / Ein ex-vivo-Verfahren zur pharmakologischen Bewertung von potentiellen Antiphlogistica anhand der ex-vivo-Bestimmung der Bildungsrate von Malondialdehyd (MDA) unter Verwendung von Ratten-Thrombozyten.

Based on a standardized in-vitro method for quantifying the activity of prostaglandin-synthetase by means of coupling malondialdehyde with 2-thiobarbituric acid the possibility of using this method also as ex-vivo technique is described. By this, more favourable prerequisites to pharmacological valuation of the effects of potential antiinflammatory substances exists compared to the application of in-vitro results, only.

[Fluorometric determination of levarterenol, epinephrine and dopamine in the urine of rats with carrageenan edema and adjuvant arthritis]. / Fluorimetrische Bestimmung von Levarterenol, Epinephrin und Dopamin im Urin von Ratten mit Carrageeninödem und Adjuvansarthritis.

After adsorption-chromatographic separation (using aluminium oxide) and chemical conversion to the corresponding trihydroxyindole derivatives, epinephrine, levarterenol and dopamine were determined fluorometrically in urine from rats. In case of carrageenin oedema, as well as during the secondary phase of adjuvant arthritis, the excretion of epinephrine and levarterenol was increased as compared to that in control animals. This difference was statistically significant. These findings can possibly be connected with an inhibitory activity of the catecholamines in inflammatory processes; as to dopamine, it seems to be of minor importance.

[The effect of cyclo-oxygenase and lipoxygenase inhibitors on anaphylactic vasodepression ex vivo in mice and rats]. / Einfluss von Cyclooxygenase- und Lipoxygenase-Inhibitoren auf die anaphylaktische Vasodepression ex vivo an Maus und Ratte.

Cyclooxygenase inhibitors (diclofenac, indomethacin, piroxicam) does not or only hardly inhibit anaphylactic vasodepression, except acetylsalicylic acid which could act as an oxygen free radical scavenger. However, the dual blocker BW 755 c strongly improves vasodepression. Pure lipoxygenase inhibitors (nordihydroguajaretic acid, oxphaman) only moderately improve vasodepression, the leukotriene antagonist FPL 55,712 is hardly effective. Obviously, endogenous prostaglandins do not and leukotrienes do take little part in the pathogenesis of anaphylactic vasodepression in the mouse and rat.

[Inhibition of arachidonic acid-induced ear edema in the mouse with lipoxygenase-, cyclo-oxygenase- and dual inhibitors]. / Hemmung des Arachidonsäure-induzierten Ohrödems der Maus durch Lipoxygenase-,Cyclooxygenase- und Dualhemmer.

The ear edema of the mouse induced by local application of arachidonic acid is suitable for in vivo differentiation of lipoxygenase (LOX) and cyclooxygenase (COX) inhibitors. LOX blockers inhibit initially and plateau-like during the first hour of the course of the edema, while COX-blockers do so mostly only initially. For practice we recommend the measurement about 60 min following edema provocation. The dual blocker of LOX and COX, BW 755 c, acts like a LOX inhibitor.

[On the antimicrobial activity of propolis and propolis constituents (author's transl)]. / Zur antimikrobiellen Wirksamkeit von Propolis und Propolisinhaltsstoffen.

After a survey of the literature on the antimicrobial activity of the bee product propolis, the authors discuss their own findings as compared to the chemotherapeutical agents streptomycin, oxytetracycline, chloramphenicol, nystatin, griseofulvin and sulphamerazine. According to the results obtained by testing 25 isolated constituents on Bacillus subtilis, Staphylococcus aureus, Candida albicans and Trichophyton mentagrophytes, the antimicrobial properties of this mixture of natural substances are mainly attributable to the flavonoids pinocembrin, galangin, pinobanksin, pinobanksin-3-acetate as well as to the p-coumaric acid benzyl ester and a caffeic acid ester mixture. None of the isolated substances was as potent as the antibiotics tested for the purpose of comparison. The relatively good antimycetic activity of the 5,7-dihydroxyflavanone pinocembrin seems noteworthy. Finally, possible mechanisms of the antimicrobial action of the flavonoids are discussed.

[In vivo testing of a 3-hydroxymethylpyridine hydrogen tartrate matrix tablet. Part 2: Comparison between the in vivo drug release from the matrix form and that from Radecol-tablets (author's transl)]. / In-vivo-Testung einer 3-Hydroxymethylpyridinhydrogentartrat-Matrixtablette. 2. Mitteilung: Vergleich der Wirkstoffliberation aus der Matrixform in vivo mit Radecol-Tabletten.

The release characteristics of 3-hydroxymethylpyridine hydrogen tartrate matrix tablets (3-hydroxymethylpyridine = HMP) were studied in vivo by determining the metabolites excreted in the urine and compared with those of commercially available Radecol tablets. After the liberation of an initial dose, the drug is release little by little from the matrix tablet. The ingested silicone matrix is not altered by the passage through the gastrointestinal tract, it is excreted unchanged. No side-effects were seen after the application of two matrix tablets (approximately 150 mg HMP).

[Simultaneous and sequential inhibition of the arachidonic acid cascade by inhibitors of phospholipase A2, cyclooxygenase and lipoxygenases in carrageenan edema and adjuvant arthritis in the rat]. / Simultane sequentielle Hemmung der Arachidonsäure-Kaskade mit Hemmern der Phospholipase A2, Cyclooxygenase und Lipoxygenasen am Carrageeninödem und der Adjuvansarthritis der ratte.

According to the aim of the simultaneous and sequential inhibition of key enzymes of the arachidonic acid cascade, combinations of inhibitors of the phospholipase A2 (PLA2), cyclooxygenase (COX) and of lipoxygenases (LOX) were administered to rats with carrageenin edema and adjuvant arthritis, respectively. While the COX inhibitors diclofenac-Na and acetylsalicylic acid in combination with PLA2 and LOX inhibitors mostly gave overadditive antiinflammatory effects in the carrageenin edema, phenylbutazone in combination at most displayed additivity. Admixture of ascorbic acid led to subadditive effects. In the adjuvant arthritic rat, the combined administration of diclofenac-Na and dexamethasone yielded additive effects, only. The same result is valid for the combination of piroxicam and a LOX inhibitor in this model. Results are discussed with respect to the mode of action of substances as well as to the model peculiarities.

[Pharmacokinetic studies of the propolis constituent pinocembrin in the rat (author's transl)]. / Pharmakokinetische Untersuchungen des Propolisinhaltsstoffes Pinocembrin an der Ratte.

The present investigation into the pharmacokinetic behaviour of the propolis constituent pinocembrin which produces a relatively good antimicrobial effect in vitro, points to possible causes of its therapeutical failure when mice infected with Candida albicans were used as a model. The biological half-life periods for the phases of invasion and elimination were 26 and 268 min, respectively. The biological availability was 25%. Almost 15% of pinocembrin are excreted unchanged in faeces and urine. Even in case of oral application of doses of up to 500 mg/kg, the serum pinocembrin concentrations did not equal the MIC (minimal inhibitor concentration) values required in vitro. A considerable first-pass effect and accelerated processes of elimination are discussed as possible causes. It appears from the present findings that pinocembrin may be utilizable only for the external treatment of stomatomycoses.

[The pharmacology of the lipoxygenase inhibitors oxphaman (1-(2,5-dihydroxybenzylidene)aminoadamantane) and oxphalin (1-(3,4-dihydroxybenzylidene)-2,4,6-trimethylaniline]. / Zur Pharmakologie der Lipoxygenasehemmer Oxphaman, 1-(2,5-Dihydroxybenzyliden)aminoadamanten, und Oxphalin, 1-(3,4-Dihydroxybenzyliden)-2,4,6-trimethylanilin.

Oxphaman and particularly oxphalin, among other phenolic azomethines, have been proven as strong inhibitors of lipoxygenases (LOX) from reticulocytes, soybean, thrombocytes as well as of quasi-LOX (hemoglobin) with IC50 values which correspond with those of known LOX inhibitors. The 5-LOX is likewise strongly, the cyclooxygenase of sheep seminal vesicles only weakly inhibited. Nevertheless, antiinflammatory effectivity was found in some carrageenin-induced inflammatory models of the rat as well as in the arachidonic acid- and croton oil-induced ear oedema of the mouse. Adjuvant arthritis, experimental pain, skin permeability and allergy models (anaphylactic paw oedema, cutaneous anaphylaxis, asthma, picryl chloride ear oedema) were not, only weakly or irregularly influenced. In the guinea pig ileum a certain antihistaminic, anticholinergic and leukotriene antagonistic activity was found. An inflammation-induced vasodepression (anaphylactic shock, dextran paw oedema. UV irradiation) was dose-dependently prevented or even reversed, obviously on the basis of oxygen radical scavenging.