Involvement of oxytocin and cholecystokinin-8 in interleukin-1 beta-induced adrenocorticotropin secretion in the rat.
It is well established that corticotropin-releasing hormone (CRH) is a principal neuropeptide which mediates the adrenocorticotropic hormone (ACTH) secretory response to interleukin (IL)-1 in the rat. It has recently been suggested that besides CRH, arginine vasopressin may also play a stimulatory role in IL-1 induced ACTH secretion. However, it remains to be elucidated whether other neuropeptides possessing an ACTH-releasing activity are involved in this neuroendocrine event. Therefore, in this study, we examined possible roles for oxytocin (OT) and cholecystokinin (CCK)-8 in the IL-1-induced ACTH response, utilizing the technique of immunoneutralization of these peptides. For comparison, we examined the effect of CRH immunoneutralization as well. Human recombinant IL-1 beta (50 ng) was given intracerebroventricularly (to the 3rd ventricle) to freely moving male rats 15 min after injecting specific antiserum against CRH, OT, or CCK-8, or normal rabbit serum (control) via the same route. As expected, anti-CRH antibody significantly suppressed the ACTH response to IL-1 beta. Interestingly, anti-OT antibody acted in the same manner, whereas anti-CCK-8 antibody did not. These results suggest that in addition to CRH and arginine vasopressin, OT may also play a significant role in mediating the IL-1 beta-induced ACTH secretion in the rat.
Watanobe
H
H
Department of Internal Medicine, Hirosaki University School of Medicine, Japan.
Sasaki
S
S
Takebe
K
K
D000324:Adrenocorticotropic Hormone / Q000097:blood / Q000378:metabolism*; D000818:Animals; D007106:Immune Sera / Q000276:immunology; D007278:Injections, Spinal; D007375:Interleukin-1 / Q000494:pharmacology*; D008297:Male; D010121:Oxytocin / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar; D012844:Sincalide / Q000494:pharmacology*; D013997:Time Factors
D007106:Immune Sera; D007375:Interleukin-1; D010121:Oxytocin; D000324:Adrenocorticotropic Hormone; D012844:Sincalide