Aberrant maternal behaviour in XXXX treated with a @entity1420 receptor antagonist during pregnancy.

@entity398 @entity1420 @entity2931 @entity19 @entity3927
The rapid onset of normal maternal behaviour after parturition in @entity19 , consisting of cleaning, warming, feeding and protection of offspring, is primed by @entity2931 , @entity1420 and @entity398 . Previous studies showed that passive transfer of monoclonal antibodies against @entity1420 significantly increases the incidence of maternal rejection of pups. To test the hypothesis that aberrant maternal behaviour is due to partial @entity1420 withdrawal leading to hormonal imbalance during late pregnancy, maternal rejection was assessed following treatment with a @entity1420 receptor antagonist. @entity3927 ( @entity3927 ) was given subcutaneously on either day 2 (100 micrograms) or day 17 (50 micrograms) of pregnancy, or on the first day of lactation (100 micrograms). Maternal behaviour was monitored twice daily for the first 6 days of lactation and pup rejection recorded for a further 15 days. Maternal rejection was significantly greater after @entity3927 administration on either day 2 or day 17 (28.6% and 38.3%) compared with controls (11.1% and 5.2% respectively). Rejection was negligible in both treated and control groups if @entity3927 was given after parturition. When mothers were treated at day 17, the length of the latent period before pups were retrieved and returned to the nest was markedly increased in @entity3927 -treated mothers (46.3 s) compared with controls (4.4 s) though the effect was transient. The results indicate that @entity3927 interferes with the hormonal priming mechanism(s) necessary for the onset of normal maternal behaviour by a receptor-mediated effect. The similarity of the present results and those obtained with anti- @entity1420 antibodies implies that receptor antagonism or antibody scavenging of @entity1420 influence a common central nervous mechanism that is essential for the normal priming process.
