Furthermore, the catalepsy induced by CCK-8-SE was of short duration.With icv. administration only 40 pmole CCK-8-NS induced significant catalepsy.When 0.2, 0.4 and 0.8 mumole/kg sc. doses of CCK-8-NS or 0.4 pmole icv. dose of CCK-8-SE or CCK-8-NS was given in combination with intraperitoneal (ip.) administration of 1.0 mg/kg haloperidol, the total duration of catalepsy was suppressed.Finally, CCK-8-SE sc. when given in combination with haloperidol ip., exerted a biphasic, synergistic-antagonistic effect on the haloperidol-induced catalepsy.