@entity4089 , as induced by pituitary homografts under the kidney capsule, was followed by an inhibition of @entity4521 self-administration in @entity35 . This effect was mimicked by intracerebroventricular (i.c.v.) injection of @entity35 @entity3695 ( @entity3695 ) or peripheral administration of a @entity4089 -inducing drug, @entity2211 . I.c.v. injection of anti- @entity3695 serum totally abolished the effect of @entity4089 on @entity4521 self-administration behavior and facilitated it in @entity35 with normal plasma @entity3695 levels. The development of tolerance to @entity1286 was facilitated in hyperprolactinaemic animals or in @entity35 injected i.c.v. with @entity35 @entity3695 . This effect was abolished in hyperprolactinaemic animals by i.c.v. injection of anti- @entity3695 serum. Furthermore, @entity35 with normal plasma @entity3695 levels showed an inhibited development of tolerance to @entity1286 after i.c.v. injection of anti- @entity3695 serum. @entity1286 -induced @entity1337 appeared to be potentiated in hyperprolactinaemic @entity35 tested in the hot-plate test. It is concluded that endogenous @entity4089 can affect opiate-induced behavioral changes in @entity35 , possibly through central mechanisms involving opioid transmission.

Effects of endogenous @entity4089 on opiate-induced behavioral changes in XXXX .

@entity4521 :: ('MESH:D003932', 'Chemical') :: ['heroin'] @entity4089 :: ('MESH:D006966', 'Disease') :: ['Endogenous hyperprolactinaemia', 'hyperprolactinaemia'] @entity1337 :: ('MESH:D000699', 'Disease') :: ['analgesia'] @entity3695 :: ('24683(Tax:10116)', 'Gene') :: ['PRL', 'prolactin'] @entity1286 :: ('MESH:D009020', 'Chemical') :: ['morphine', 'Morphine'] @entity2211 :: ('MESH:D004294', 'Chemical') :: ['domperidone'] @entity35 :: ('10116', 'Species') :: ['rat', 'rats']
@entity35 :: (10116,Species) :: ['rats']
