The antiphospholipid syndrome in pregnant rabbits and their offspring. Neuropathological aspects.

OBJECTIVE Although the obstetric consequences of antiphospholipid syndrome (APS) in pregnant rabbits have been described, there are no data on the serological and neuropathological aspects of the syndrome in their offspring. It would also be interesting to recognize whether the CNS abnormalities in rabbit fetuses relate to placental damage or depend on the antiphospholipid antibodies, transmitted from the pregnant animal through the placenta to the fetal serum. MATERIAL AND METHODS A post-mortem neuropathological examination was done on 36 adult female New Zealand rabbits, and their offspring (100 fetuses). The material was divided into 4 groups: Group I--26 pregnant rabbits with experimental APS, Group IC 10--pregnant rabbits without APS (control group I), Group II--64 fetuses derived from animals included in Group I, and Group IIC--36 fetuses derived from individuals included in Group IC (control group II). The platelet count, activated partial thromboplastin time (APTT), antiplatelet antibodies in serum and coated on the platelets were evaluated to identify the APS in adult rabbits and their offspring. RESULTS A significantly higher number of fetuses demonstrating weaker vitality and shorter survival time was observed in Group II. The percentage of dead and reabsorbed fetuses was also considerably higher in Group II. The serum markers of APS occurred both in Group I and II while the neuropathological evidences of APS: the thrombo-necrotic and inflammatory changes were found exclusively in APS pregnant animals. Moreover, cytoarchitecture of the fetal brains was intact. There were no disturbances in neuronal migration and abnormalities of cytodifferentiation. CONCLUSIONS 1. The antiphospholipid syndrome in pregnant rabbits results in serological markers of the syndrome in their offspring. 2. The central nervous system of fetuses delivered from pregnant rabbits with the antiphospholipid syndrome remains intact despite the serological markers of the syndrome in fetus circulation. 3. The miscarriages in pregnant rabbits with the antiphospholipid syndrome depend rather on placental pathology related to the syndrome than on the syndrome per se transmitted from adult females to fetal circulation.