The thymus-adrenal connection: thymosin has corticotropin-releasing activity in primates.
Endotoxin-free thymosin fraction 5 elevated corticotropin, beta-endorphin, and cortisol in a dose- and time-dependent fashion when administered intravenously to prepubertal cynomolgus monkeys. Two synthetic component peptides of thymosin fraction 5 had no acute effects on pituitary function, suggesting that some other peptides in thymosin fraction 5 were responsible for its corticotropin-releasing activity. In agreement with these observations, total thymectomy of juvenile macaques was associated with decreases in plasma cortisol, corticotropin, and beta-endorphin. These findings indicate that the prepubertal primate thymus contains corticotropin-releasing activity that may contribute to a physiological immunoregulatory circuit between the developing immunological and pituitary-adrenal systems.
D000324:Adrenocorticotropic Hormone / Q000097:blood*; D000818:Animals; D004305:Dose-Response Relationship, Drug; D004723:Endorphins / Q000097:blood; D005260:Female; D006854:Hydrocortisone / Q000097:blood; D007700:Kinetics; D008252:Macaca fascicularis; D000077596:Thymalfasin; D013934:Thymectomy; D013947:Thymosin / Q000031:analogs & derivatives / Q000494:pharmacology*; D013950:Thymus Gland / Q000502:physiology*; D001615:beta-Endorphin; D000099201:Thymosin beta(4)
D000324:Adrenocorticotropic Hormone; D004723:Endorphins; D006854:Hydrocortisone; D000077596:Thymalfasin; D013947:Thymosin; D001615:beta-Endorphin; D000099201:Thymosin beta(4)