Endocrine, behavioral and autonomic effects of neuropeptide AF.
The actions of neuropeptide AF (NPAF), on the hypothalamic-pituitary-adrenal (HPA) axis, behavior and autonomic functions were investigated. NPAF (0.25, 0.5, 1, 2 nmol) was administered intracerebroventricularly to rats, the behavior of which was monitored by means of telemetry, open-field (OF) observations and elevated plus-maze (EPM) tests. The temperature and heart rate were recorded by telemetry, and the plasma ACTH and corticosterone levels were used as indices of the HPA activation. The dopamine release from striatal and amygdala slices after peptide treatment (100 nM and 1 microM) was measured with a superfusion apparatus. To establish the transmission of the HPA response, animals were pretreated with the corticotrophin-releasing hormone (CRH) receptor antagonist antalarmin or astressin 2B (0.5 nmol). In the OF test, the animals were pretreated with antalarmin or haloperidol (10 microg/kg), while in the EPM test they were pretreated with antalarmin or diazepam (1 mg/kg). NPAF stimulated ACTH and corticosterone release, which was inhibited by antalarmin. It activated exploratory locomotion (square crossings and rearings) and grooming in OF observations, and decreased the entries to and the time spent in the open arms during the EPM tests. The antagonists inhibited the locomotor responses, and also attenuated grooming and the EPM responses. NPAF also increased spontaneous locomotion, and tended to decrease the core temperature and the heart rate in telemetry, while it augmented the dopamine release from striatal and amygdala slices. These results demonstrate, that acute administration of exogenous NPAF stimulates the HPA axis and behavioral paradigms through CRH and dopamine release.
Jászberényi
Miklós
M
Department of Pathophysiology, University of Szeged, Szeged, Hungary.
Bagosi
Zsolt
Z
Thurzó
Balázs
B
Földesi
Imre
I
Szabó
Gyula
G
Telegdy
Gyula
G
D000324:Adrenocorticotropic Hormone / Q000097:blood; D000818:Animals; D014151:Anti-Anxiety Agents / Q000008:administration & dosage; D001522:Behavior, Animal / Q000187:drug effects*; D001831:Body Temperature / Q000187:drug effects; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D002491:Central Nervous System Agents / Q000008:administration & dosage*; D003345:Corticosterone / Q000097:blood; D003975:Diazepam / Q000008:administration & dosage; D004298:Dopamine / Q000378:metabolism; D018492:Dopamine Antagonists / Q000378:metabolism; D006220:Haloperidol / Q000008:administration & dosage; D006339:Heart Rate / Q000187:drug effects; D007030:Hypothalamo-Hypophyseal System / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D009842:Oligopeptides / Q000008:administration & dosage*; D010446:Peptide Fragments / Q000008:administration & dosage; D010456:Peptides, Cyclic / Q000008:administration & dosage; D010913:Pituitary-Adrenal System / Q000187:drug effects*; D011743:Pyrimidines / Q000008:administration & dosage; D011758:Pyrroles / Q000008:administration & dosage; D051381:Rats; D017208:Rats, Wistar; D018019:Receptors, Corticotropin-Releasing Hormone / Q000037:antagonists & inhibitors
D014151:Anti-Anxiety Agents; D002491:Central Nervous System Agents; D018492:Dopamine Antagonists; D009842:Oligopeptides; D010446:Peptide Fragments; D010456:Peptides, Cyclic; D011743:Pyrimidines; D011758:Pyrroles; D018019:Receptors, Corticotropin-Releasing Hormone; C103016:antalarmin; C528574:astressin-2B; D000324:Adrenocorticotropic Hormone; C061209:A18Famide; D006220:Haloperidol; D003975:Diazepam; D004298:Dopamine; D003345:Corticosterone