Lupus serum and normal human serum contain anti-DNA antibodies with the same idiotypic marker.

We have previously shown that serum from patients with active SLE contain high levels of Id-16/6 and anti-DNA antibodies. In this study we investigated whether serum Id 16/6 is related to anti-DNA antibodies. Sera from 12 patients with active SLE were absorbed individually with poly(dT) cellulose (to purify anti-DNA antibodies) and rabbit (R) anti-Id-16/6 Sepharose (to purify Id 16/6 Ig).

Biological profile of a bioactive aortic substance (BAS), released by vessel rings from indomethacin-treated rats.

The biological activity of a stable unknown material(s), generated by aortic rings (bioactive aortic substance = BAS) isolated from rats injected with a high dose of indomethacin, was explored on contractions of several smooth muscle preparations from normal rats and its effects compared with those elicited by prostacyclin (PGI2) or by 6-keto-prostaglandin F1 alpha (6-k-PGF1 alpha). The BAS evoked, as did PGI2 or 6-k-PGF1 alpha, positive inotropism in strips from rat stomach, ileum and urinary bladder, but failed to influence uterine contractions as did prostacyclin or its non-enzymatic metabolite. When tested in rat aortic strips both, PGI2 and the BAS produced relaxation, whereas 6-k-PGF1 alpha was not active.

Lipoxygenase inhibitors alter aggregation and adhesiveness of human blood platelets from aspirin-treated patients.

The influences of arachidonic acid (AA) and of inhibitors of lipoxygenases (eicosatetraynoic acid-ETYA- and nordihydroguaiaretic acid -NDGA-) on platelet aggregation evoked by collagen or adenosinediphosphate (ADP) as well as platelet adhesiveness to collagen of platelet-rich-plasma (PRP) from aspirin-treated patients were explored. ETYA or NDGA (10(-8) and 10(-7) M) clearly diminished the per cent aggregation evoked by collagen or ADP and delayed its onset. On the other hand AA (0.