The effects of drugs on leucocyte changes following the injection of antigen into the peritoneal cavities of actively sensitised rats

Abstract

The injection of antigen into the peritoneal cavities of actively sensitised rats produced an immediate reaction characterised by an increase in concentrations in the peritoneal fluids, collected 5 min later, of extravasated dye labelled plasma proteins, histamine and slow reacting substance of anaphylaxis (SRS-A). Changes were also produced in the numbers of leucocytes in the blood and peritoneal cavity. 5 min after antigen challenge there was a reduction in the number of cells that could be washed from the peritoneal cavity. 4 h after antigen there was an increase in numbers of neutrophils both in the blood and peritoneal washings and these fell to the levels in control rats at 24 h. 24 h after antigen, and continuing for 72 h, there was an increase in numbers of eosinophils and mononuclear cells in the peritoneal washings. The rats were injected intravenously with sephadex particles to produce a blood eosinophilia at the time of antigen challenge, this increased the numbers of eosinophils migrating into the peritoneal cavity but had no effect on antibody levels, the numbers of other leucocytes or on the immediate reaction. An inhibitor of lipoxygenase and cyclo-oxygenase metabolism of arachidonic acid, phenidone, at 100 mg/kg p.o., inhibited SRS-A release to control levels, in the immediate reaction, but had no effect on the leucocyte changes. The glucocorticosteroid, dexamethasone, at doses of 0.1 and 1 mg/kg p.o., produced little inhibition of SRS-A release but significantly inhibited neutrophil, eosinophil and mononuclear cell infiltration into the peritoneal cavity.(ABSTRACT TRUNCATED AT 250 WORDS)

Antigen challenge induces pulmonary airway eosinophil accumulation and airway hyperreactivity in sensitized guinea‐pigs: the effect of anti‐asthma drugs

“…It is interesting to note that stimuli such as ozone Holroyde & Norris, 1988) (Winqvist et al, 1982). Hypodense eosinophils exhibit greater oxygen consumption (Winqvist et al, 1982), are more reactive to a variety of stimuli, thus generating greater quantities of leukotriene C4 (LTC4), and kill parasite larvae more actively (Rothenberg et al, 1988 (Murlas & Roum, 1985;, Sanjar et al, 1990, rats (Spicer et al, 1985) or man (Ohman et al, 1972;Horn et al, 1975;Gobel, 1979;Diaz et al, 1984). It was surprising that none of the drugs used in this study inhibited airway hyperreactivity.…”

Eosinophil accumulation in pulmonary airways of guinea‐pigs induced by exposure to an aerosol of platelet‐activating factor: effect of anti‐asthma drugs

“…On the other hand, mepyramine, indomethacin or salbutmol were without effect. Cyclo-oxygenase inhibitors do not inhibit eosinophil accumulation (Spicer et al, 1985;Fugner, 1989) and anti-histamines are not considered to affect eosinophil accumulation, since most experiments using antigen as the stimulus are conducted under cover of an antagonist of histamine to prevent death from anaphylaxis. The action of /1-adrenoceptor agonists is more controversial with one study reporting an inhibition of antigen-induced eosinophilia by fenoterol (Fugner, 1989) and another confirming our finding of no inhibition with albuterol (Hutson et al, 1988).…”

Inhibition of PAF-induced eosinophil accumulation in pulmonary airways of guinea pigs by anti-asthma drugs.

“…Studies in the rat (19), guinea pig (6) and mouse (20) indicate that drugs such as ketotifen or cromoglycate may achieve inhibition irrespective of the stimulus used to induce eosinophil accumu lation. There are few clinical reports on the effect of anti-asthma drugs on eosinophils in asthma.…”