Abstract
The effects of oestradiol and the oestrogen receptor antagonist ICI 182,780 were investigated on the DTH index, serum IgG and IgM levels and spleen weight in female BALB/c and MRLIMP-Ipr/lpr mice. At six weeks, the mice were ovariectomisecl, and one week later, over a four-week period, given biweekly s.c. doses of (i) 5μJ l of oli ve oil, or (i i) 5 μ1 of oil containing 3.2 μg of 17β-oestradiol (E2), or (iii) 5 μl of oil containing (3.2 μl of E2 + ICI 182,780 , at a dose of 30 mg/kg), or (iv) the same dose of ICI 182,780 alone. E2 significantly raised the DTH index in BALB/c mice; this effect was prevented if ICI 182,780 was included in the injectio n . The DTH index in MRL mice was unaffected by any of the treatments. All steroid u·eatments raised serum IgG levels in BALB/c mice, but those in sera of MRL were un affected and were significantly higher than those measured in BALB/c mice . ICI 182,780 depressed TgM in BALB/c mice, while all steroidtreatments increased JgM in MRL mice. ICI 182,780 de pressed spleen weights in both strains. Oes u·ogen may influence Bcell functiontlu·ough ICI 182,780-se nsitive receptors, and ICI 182,780 may have agonist actions on the immune system. (200 words)
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