MIF-1 attenuates apomorphine stereotypies in adult rats after neonatal 6-hydroxydopamine.
Since prolyl-leucyl-glycinamide (MIF-1) modifies the behavior of adult rats after treatment with neuroleptics, we examined whether MIF-1 would also modify adult behavior after treatment of neonatal rats with 6-hydroxydopamine (6-OHDA). Rats received 6-OHDA (100 micrograms i.c.v.) or diluent at 3 days after birth and either MIF-1 (2.0 mg/kg per day s.c. x 10 days) or diluent beginning at 28 or 29 days after birth. At 5 weeks, a low dose (0.1 mg/kg s.c.) of apomorphine increased the distance traveled, time in ambulation, number of stereotypic movements, and number of movements per time in stereotypy, but decreased the time in stereotypy in the 6-OHDA group. MIF-1 (x 7 or 8 days) showed a tendency to attenuate the increased number of movements and significantly (P less than 0.05) reduced all of the other effects of neonatal 6-OHDA. Behavior induced by higher doses of apomorphine in the 6-OHDA group (reduced licking and head nodding; increased paw treading, taffy pulling and self-biting) were not attenuated by MIF-1. At 38 or 39 days, total in vitro binding of [3H]SCH-23390 and [3H]spiroperidol to striatal homogenates was not altered in any of the groups. The findings demonstrate that specific early developmental alterations in apomorphine-induced behaviors can be modified by treatment of adult rats with MIF-1, even in the absence of overt changes in the binding of striatal dopamine D-1 and D-2 receptors.
Kostrzewa
R M
RM
Quillen-Dishner College of Medicine, East Tennessee State University, Johnson City 37614.
White
T G
TG
Zadina
J E
JE
Kastin
A J
AJ
D000818:Animals; D000831:Animals, Newborn / Q000502:physiology*; D001058:Apomorphine / Q000494:pharmacology*; D001552:Benzazepines / Q000494:pharmacology; D003342:Corpus Striatum / Q000187:drug effects / Q000378:metabolism; D005260:Female; D006892:Hydroxydopamines / Q000494:pharmacology; D009075:MSH Release-Inhibiting Hormone / Q000378:metabolism / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects; D016627:Oxidopamine; D011247:Pregnancy; D051381:Rats; D011954:Receptors, Dopamine / Q000378:metabolism; D013239:Stereotyped Behavior / Q000187:drug effects*
D001552:Benzazepines; D006892:Hydroxydopamines; D011954:Receptors, Dopamine; D016627:Oxidopamine; D009075:MSH Release-Inhibiting Hormone; D001058:Apomorphine