Influence of ricinoleic acid on the contractions elicited by PGE2 on the guinea-pig ileum

The effect of ricinoleic acid on prostaglandin E2 (PGE2)-evoked contractions was studied on guinea-pig isolated ileum. Addition of ricinoleic acid (10 micrograms ml-1) to the organ bath increased the amplitude of the PGE2-evoked responses. Ricinoleic acid (10 micrograms ml-1) also sensitized the guinea-pig isolated ileum to acetylcholine and histamine. The effect of the ricinoleic acid was greatly reduced by indomethacin either in-vivo (10 mg ml-1) or in-vitro (2 micrograms ml-1).

Antipyretic and antibacterial actions of Teucrium polium (L.)

The antipyretic and antibacterial activities of the ethanolic extract of the flowering tops of Teucrium polium (L.) were been studied. The extract was effective against both yeast and carrageenin pyrexia in rats. It also exhibited a marked antibacterial action against both gram positive and gram negative organisms and was found to be non toxic in acute studies.

Chemical composition and anti-inflammatory activity of an alcoholic extract of Teucrium polium L

In the Teucrium polium L. were identified, by gaschromatographic and spectroscopic techniques (1H-NMR and MS), beta-sitosterol, stigmasterol, campesterol, brassicasterol and clerosterol. In the aqueous phase of the alcoholic extract were identified glucose, fructose, raffinose and rhamnose by PC on Watmann paper Number 5. Anti-inflammatory activity was tested using male Wistar rats against carrageenin-induced paw oedema. All tested extract shown a sufficient pharmacological activity compared to that of indomethacine.

Phytotherapeutic profile of some plants used in folk medicine

The effect of nine vegetable extracts was evaluated on the carrageenin-induced oedema in the rat. Our results show that the above extracts are able to exert - at different degree - a very marked decrease of the inflammed site related to the presence in the considered plants of several active biologically compounds as sterols and flavonoids. Preliminary chemical analysis of these vegetables are also reported.

Effect of indomethacin on aloin and 1,8 dioxianthraquinone-induced production of prostaglandins in rat isolated colon

The effect of aloin and 1,8 dioxyanthraquinone on the release of prostaglandin-like material (PG) from rat isolated colon has been investigated. Orally administered aloin and 1,8 dioxyanthraquinone stimulates PG production by subsequently isolated segments of colon. Indomethacin was able to prevent this increased production of PG. These results suggest that the laxative properties of aloin and 1,8 dioxyanthraquinone may depend, at least in part, on increased prostaglandin synthesis by the intestinal tissue.

Enhancement by levamisole of the contractions induced by prostaglandin E2 in the guinea-pig isolated ileum

The effect of levamisole on prostaglandin E2 (PGE2)-evoked contractions was studied on guinea-pig isolated ileum. Addition of levamisole (10 micrograms/ml) to the organ bath produced a pronounced increase in the amplitude of the PGE2-evoked responses. Levamisole (10 micrograms/ml) also sensitized the guinea-pig isolated ileum to 5-hydroxytryptamine and bradykinin, but not to histamine. The effect of the levamisole was not due to stimulation of autonomic ganglia or cholinergic activity since it was unaffected by hexamethonium or atropine, but it was prevented by indomethacin.

Some pharmacological properties of tiopronin

Tiopronin (50 mg/kg) and D-penicillamine (50 mg/kg) do not exhibit anti-inflammatory effects in classic animal models (carragenin oedema, granuloma cotton pellets) but suppress pertussis vaccine oedema, an immunological model, when given with a long-lasting dosing regime. Tiopronin and D-penicillamine also fail to inhibit PG release by phagocytosing leucocytes when the concentrations used were in the same range as human blood levels (5-15 micrograms/ml). Indomethacin (1, 3 and 5 mg/kg) instead significantly inhibits both the in vivo and in vitro models considered. This may imply a different mode of action of both tiopronin and D-penicillamine from indomethacin. Tiopronin also possesses similar effects to D-penicillamine suggesting that their overall anti-rheumatic action may have common elements.

Endogenous inhibitor of prostaglandin biosynthesis in inflammation

Rat serum exhibits a concentration-related inhibition of PG biosynthesis by rat peritoneal leucocytes phagocytosing killed bacteria. The serum inhibitory potency is increased by inducing carrageenan foot oedema in animals whereas it is not altered by dextran oedema. The increase of the inhibitory activity of serum from carrageenan-treated rats develops in a time-dependent way reaching its maximum at 24 h. Since the increased inhibitory activity does not occur following indomethacin administration we suggest that PG formation at the inflammatory site may stimulate the ability of serum to inhibit PG biosynthesis.

Anti-inflammatory properties of griseofulvin

Anti-inflammatory activity of griseofulvin has been investigated in comparison with indomethacin and flufenamic acid. In vitro, griseofulvin has been proved the most effective of these agents in suppressing the contractions of smooth muscle preparations induced by a variety of proposed mediators of inflammation, i.e. histamine, 5-hydroxy-tryptamine, bradykinin and prostaglandin E2. In vivo, griseofulvin was unable to modify dextran oedema but suppressed carrageenin oedema, although its activity was poor when compared to that exhibited by indomethacin and flufenamic acid. When tested in rat pleurisy induced by dextran or homologous serum griseofulvin was able to prevent polymorph migration into the pleural space while mononuclears remained virtually unaffected. In contrast indomethacin and flufenamic acid mainly suppressed mononuclear migration while polymorphs resulted only slightly affected. Similar results have been exhibited by the drugs when tested on mononuclear turnover in pleural cavities from normal rats. Results are discussed in the light of the clinically established ability of griseofulvin to prevent cutaneous inflammatory reactions as well as of its effectiveness in the treatment of several polyarthritic syndromes.

Effects of modification of intracellularcyclic AMP levels on the imediate hypersensitivity reaction in vivo

Experiments were performed to study the effects of agents that elevate endogenous cyclic AMP levels on the progression of a reverse passive Arthus reaction in the pleural cavity of rats. Three hours after the onset of the reaction a marked reduction in histamine release was observed which correlated well with increases in cellular cyclic AMP concentration. The results at 6 hr suggested a relationship between cyclic AMP and leucocyte PGE, the latter being reduced dramatically both in the cells and in the fluid exudate by agents that elevate cyclic AMP. It was concluded that cyclic AMP may play an important regulatory role in vivo in the release of inflammatory mediators from leucocytes.

Pharmacological mediators of various immunological and non-immunological inflammatory reactions produced in the pleural cavity

Intrapleural exudates have been produced in rats and guinea-pigs using calcium pyrophosphate, cell mediated immunity, reversed passive Arthus reaction and carrageenan. The intracellular concentration of various pharmacological mediators has been measured at different times during the evolution of these inflammatory responses. These have been correlated with volume of exudate and cellular migration. The significance of these findings has been discussed and the possible application to the search for new anti-inflammatory agents and their use in diagnostic procedures.

Quantitative studies on cell-mediated immunity in the pleural cavity of guinea-pigs

Intrapleural injection of PPD into CFA-sensitised guinea-pigs produced a reaction having many of the characteristics of classical delayed hypersensitivity. Quantitative investigations of the time course of this reaction showed that it was typified by an initial delay in the onset of increased vascular permeability, which reached its peak between 12 and 18 hr. The cellular response in the pleural cavity followed a similar pattern, attaining maximum levels between 18 and 24 hr. Mononuclear cells dominated the reaction from 12 to 48 hr. The histological appearance of the lung tissue was also studied. Treatment with Cobra venom factor, a complement-depleting agent, failed to modify this reaction. Cyclic AMP levels were assayed for both the cellular and cell-free exudates.

Enhancement of carrageenin foot oedema by 1,10 -phenanthroline and evidence for the bradykinin as endogenous mediator

Carrageenin oedema in enhanced by the simultaneous injection in the rat paw of 1,10-phenanthroline, a kininase inhibitor. The analysis of the time-course of this enhancement showed that the maximal effect was observed about 3 hours after the injection. This enhancement was also present when the oedema-producing agent was cellulose sulphate, a kinin-releasing compound. On the contrary, oedema induced by eggwhite as well as by dextran, which are mainly mediated by histamine and 5-hydroxytryptamine, were unaffected by 1,10-phenanthroline. These results further support the role of kinins in the pathogenesis of carrageenin oedema.

A model for the quantitative study of Arthus (immunologic) hypersensitivity in rats

A model of reverse passive Arthus (RPA) reaction in the pleural cavity of rats is described. The time course of development of exudate and migration of cells has been examined. It has been found to be complement dependent and dominated by polymorphonuclear cells. The reaction reaches a peak around 6 hours after challenge. Cyclic AMP levels have been measured both intracellularly and extracellularly and have been found to persist at high levels after the waning of the reaction.

Further studies on carrageenan-induced pleurisy in rats

A study has been made of the exudate provoked by intrapleural carrageenan in rats. Various parameters have been measured including volume of exudate, numbers and types of cells. Pharmacological assay has shown the early release of histamine and 5HT into the exudate followed at later times by a release of prostaglandins, and a second release of histamine. The role of complement has been studied. Intrapleural injection of carrageenan after complement depletion produced a reduced migration of polymorphonuclear cells and also a reduction in volume of exudate. Prostaglandins remained unaffected by this treatment.

Calcium pyrophosphate-induced pleurisy in rats: a new model of acute inflammation

A model is described of acute inflammation in the pleural cavity of rats using calcium pyrophosphate as the irritant. This model would seem to simulate the pseudogout syndrome. It has been shown to be acute in onset, dominated by polymorphonuclear cells, complement independent. The advantage of the model is that volume of exudate, numbers and types of cells may be quantitated. Prostaglandins and cyclic AMP have been measured in the migrating cells. The significance of these findings has been discussed.