J. P. Giroud

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.

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.

The mast cells of the newborn rat diaphragm and their response to histamine liberators

The mast cell population of rat diaphragm was estimated between birth and adulthood and found to rise with an increase in the age of rat studied. Degranulation of these cells was observed in rats from all age groups, following treatment with compound 48/80 and dextran. The association of mast cells with the blood vessel wall in adult rat diaphragm was not observed in the comparable tissues of newborn rats. These findings are discussed in relationship to the poor vascular permeability reactions exhibited by newborn and young rats.

The pharmaco-cellular assessment of slow acting anti-inflammatory agents

The accumulation of macrophages on glass coverslips inserted subcutaneously in mice has been used to demonstrate an anti-inflammatory action of a mixture of metallic oxides (Neoarth®). The effect is apparent only after some delay and other tests i.e. carrageenan foot oedema and adjuvant arthritis confirmed the delayed nature of this compounds anti-inflammatory effect. Attention is drawn to the possible value of the subcutaneous coverslip model in detecting delayed anti-inflammatory effects that might be missed in other simple screening tests.