Behavioral changes induced by the thyrotropin-releasing hormone analogue, RGH 2202.
The behavioral activity of the thyrotropin-releasing hormone (TRH) analogue, L-6-ketopiperidine-2- carbonyl-leucyl-L-prolinamide (RGH 2202), has been studied in the rat. The number of errors in a radial maze test was reduced after acute intraperitoneal (IP) injection of RGH 2202 at the dose of 5 or 10 mg/kg. Grooming activity was increased with a lower dose, 1 mg/kg. Hypoxia-induced amnesia, as assessed with active and passive avoidance behavior tests, was reversed in rats treated with 5 or 10 mg/kg of the drug. The loss of learning and memory capacity shown by aged rats in the same behavioral tests was also reduced after injection of RGH 2202. In a test for sexual activity of male rats, the higher dose of the drug induced a facilitation of mounting and ejaculations, while smaller doses were ineffective. The rotorod test revealed a decreased number of falls in animals treated with 5 or 10 mg/kg of RGH 2202. In all behavioral tests, the same doses of natural thyrotropin-releasing hormone (TRH) were less effective, indicating that this analogue may be qualified as a potentially active drug in human pathologies.
Drago
F
F
Institute of Pharmacology, University of Catania Medical School, Italy.
Grassi
M
M
Valerio
C
C
Coppi
G
G
Lauria
N
N
Nicotra
G C
GC
Raffaele
R
R
D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001522:Behavior, Animal / Q000187:drug effects*; D004193:Discrimination Learning / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D006120:Grooming / Q000187:drug effects; D008297:Male; D008568:Memory / Q000187:drug effects; D051381:Rats; D011919:Rats, Inbred Strains; D012726:Sexual Behavior, Animal / Q000187:drug effects; D013037:Spatial Behavior; D013973:Thyrotropin-Releasing Hormone / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000494:pharmacology
D013973:Thyrotropin-Releasing Hormone; C055448:posatirelin