Various peptide hormones appear to exert behavioral and pharmacologic effects apart from their classical endocrine actions. Thyrotropin-releasing hormone (TRH), for example, antagonizes the sedation and hypothermia produced by barbiturate and other depressant drugs and de Wied has shown that ACTH 4-10, TRH, LHRH and certain related substances show some activity in inhibition of extinction of a pole-jumping avoidance response in the rat. These data provided the impetus for screening ACTH 4-10, LHRH, and related peptides for analeptic activity. ACTH 4-10 and ACTH 4-7 were inactive in antagonizing pentobarbital whether administered peripherally or centrally. ACTH 4-7 amide and 4-Met(O2),8-D-Lys,9-Phe-ACTH 4-9 were active regardless of route of administration LHRH and two tripeptide fragments (Glu-His-Trp-NH2 and pGlu-His-Phe-NH2) showed analeptic activity only after intracisternal administration. Thus, sme peptide fragments related to ACTH 4-10 and LHRH were shown to share were shown to share to some degree the analeptic properties previously demonstrated for TRH.
- ACTH peptides
- Luteinizing hormone-releasing hormone
- Sodium pentobarbital
- Thyrotropin releasing hormone
ASJC Scopus subject areas
- Behavioral Neuroscience