Open AccessEffects of Cholecystokinin Tetra and Octa Peptides on Locomotor Activity in Mice
Author(s) -
Yasuo Takeda,
Yukio Takáno,
Hiro-o Kamiya
Publication year - 1986
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - English
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.42.145
Subject(s) - tetra , cholecystokinin , chemistry , locomotor activity , medicine , pharmacology , stereochemistry , endocrinology , biology , medicinal chemistry , biochemistry , receptor
Intraperitoneal injection of cholecystokinin octapeptide (10 and 100 micrograms/kg, i.p.), but not the tetra-peptide (1 mg/kg, i.p.), into mice significantly reduced spontaneous locomotor activity in a dose-dependent manner. The increase in locomotor activity induced by methamphetamine (1 mg/kg, i.p.) and thyrotropin-releasing hormone (5 mg/kg, i.p.) was significantly reduced by cholecystokinin peptides. However, the inhibitory effects of these peptides differed. Neither the tetra nor octa peptide influenced the increased locomotor activity induced by nomifensine (5 mg/kg, i.p.), apomorphine (3 mg/kg, i.p.) or scopolamine (2 mg/kg, i.p.). Thus, these cholecystokinin peptides seem to selectively antagonize increased locomotor activity via the presynaptic dopaminergic system.