TY - JOUR
T1 - Regulation of rat adrenal neuropeptide Y (NPY) content: Effects of ACTH, dexamethasone and hypophysectomy
AU - Hinson, J.P.
AU - Renshaw, D.
AU - Cruchley, A.T.
AU - Kapas, S.
PY - 1998/9/25
Y1 - 1998/9/25
N2 - While the presence of neuropeptide Y (NPY) in the adrenal cortex is well established, little is known about its regulation. In the present study the involvement of the pituitary gland in the regulation of rat adrenal NPY content was investigated. Rats were subjected to one of the following treatments: hypophysectomy, sham operation, ACTH, the synthetic glucocorticoid, dexamethasone, dexamethasone plus ACTH, or saline control. The immunoreactive NPY (irNPY) content of both capsule/zona glomerulosa and inner zone/medulla fractions were estimated by radioimmunoassay. Treatment with ACTH caused a significant decrease in both the capsular/zona glomerulosa and the inner zone/medulla irNPY content compared with controls, while hypophysectomy resulted in a significant increase in adrenal irNPY. Dexamethasone treatment caused a significant increase in capsular irNPY, which was reversed by simultaneous administration of ACTH. In the medulla, however, dexamethasone treatment significantly decreased irNPY content. These results suggest that there is differential regulation of adrenal irNPY content, with irNPY in the zona glomerulosa regulated directly by ACTH, while the irNPY content of the inner zones/medulla is regulated by glucocorticoids.
AB - While the presence of neuropeptide Y (NPY) in the adrenal cortex is well established, little is known about its regulation. In the present study the involvement of the pituitary gland in the regulation of rat adrenal NPY content was investigated. Rats were subjected to one of the following treatments: hypophysectomy, sham operation, ACTH, the synthetic glucocorticoid, dexamethasone, dexamethasone plus ACTH, or saline control. The immunoreactive NPY (irNPY) content of both capsule/zona glomerulosa and inner zone/medulla fractions were estimated by radioimmunoassay. Treatment with ACTH caused a significant decrease in both the capsular/zona glomerulosa and the inner zone/medulla irNPY content compared with controls, while hypophysectomy resulted in a significant increase in adrenal irNPY. Dexamethasone treatment caused a significant increase in capsular irNPY, which was reversed by simultaneous administration of ACTH. In the medulla, however, dexamethasone treatment significantly decreased irNPY content. These results suggest that there is differential regulation of adrenal irNPY content, with irNPY in the zona glomerulosa regulated directly by ACTH, while the irNPY content of the inner zones/medulla is regulated by glucocorticoids.
KW - Zona glomerulosa
KW - Adrenal medulla
KW - HPA axis
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-0032566795&partnerID=MN8TOARS
U2 - 10.1016/S0167-0115(98)00065-2
DO - 10.1016/S0167-0115(98)00065-2
M3 - Article
SN - 0167-0115
VL - 75-76
SP - 75
EP - 76
JO - Regulatory Peptides
JF - Regulatory Peptides
ER -