Dermatosis in magnesium-deficient hairless rats has been described as a reproducible model of skin inflammation. It was therefore felt of interest to search for the effects of various anti-inflammatory compounds on this model. Results showed that 1) Dexamethasone acetate completely abolished the rash, 2) Indomethacin, a Non-Steroidal Anti-Inflammatory Drug (NSAID), inhibitor of the cyclooxygenase pathway was quite inactive, 3) Benoxaprofen, a NSAID inhibitor of both cyclooxygenase and lipoxygenase pathways only slightly modified the development of the pathology. Activity of steroidal anti-inflammatory drugs on this model may be related to their immunosuppressive effects.

Hairless rats with dermatosis induced with a poor magnesium diet were previously shown to bear biochemical and immunological abnormalities. It was therefore felt of interest to investigate the spleen cells proliferative responses from these rats, both in the rash and the remission phases, when testosterone and parathormone plasma levels were also determined. Results showed that proliferative responses to mitogens and PTH levels were inversely related to the intensity of the dermatosis, whereas testosterone levels were more or less decreased. The role of 1.25 dihydroxyvitamin D3 in these modifications is questionable.

MRL - lpr/lpr (MRL/l) mice spontaneously develop an autoimmune pathology including arthritic lesions. SR 41319, a bisphosphonate, having previously shown to be active in in vitro and in vivo models of arthritis, the aim of this study was to search for its possible effect on the pathology of the MRL/l mice. Results showed that SR 41319 reduced the severity of the disease in its early stages and increased mean life span. Further investigation would be necessary to define the effect of the drug during later stages when major changes in immune status occurred.