TY - JOUR
T1 - Effect of gonadal steroids on hypothalamus and anterior pituitary endo-oligopeptidase B (proline-endopeptidase) activity in castrated female rats
AU - López-Jaramillo, P.
AU - Antunes-Rodrigues, J.
AU - Camargo, A. C.M.
PY - 1984
Y1 - 1984
N2 - In the present study we investigated the possible participation of endo-oligopeptidase B (poline-endopeptidase) in the control of gonadotrophin secretion through the control of LH-RH inactivation. This enzyme selectively hydrolyzes the Pro9-Gly10-NH2 peptide bond of LH-RH, thereby inactivating this substance. The enzyme activity was evaluated using a specific colorimetric substrate, i.e., Z-Gly-Pro-SM. Female adult Wistar rats were submitted to castration, experimental situations that are known to produce changes in gonadotrophin secretion. Hypothalamic and pituitary endo-oligopeptidase B activity was shown to be present predominantly in the soluble fraction of the enzyme preparations. The results also indicated that endo-oligopeptidase B activity adult female rat pituitary decreased after castration and increased after administration of estradiol and progesterone to castrated animals. The present results lead us to suggest that anterior pituitary endo-oligopeptidase B may be related to the control gonadotrophin secretion in female rats.
AB - In the present study we investigated the possible participation of endo-oligopeptidase B (poline-endopeptidase) in the control of gonadotrophin secretion through the control of LH-RH inactivation. This enzyme selectively hydrolyzes the Pro9-Gly10-NH2 peptide bond of LH-RH, thereby inactivating this substance. The enzyme activity was evaluated using a specific colorimetric substrate, i.e., Z-Gly-Pro-SM. Female adult Wistar rats were submitted to castration, experimental situations that are known to produce changes in gonadotrophin secretion. Hypothalamic and pituitary endo-oligopeptidase B activity was shown to be present predominantly in the soluble fraction of the enzyme preparations. The results also indicated that endo-oligopeptidase B activity adult female rat pituitary decreased after castration and increased after administration of estradiol and progesterone to castrated animals. The present results lead us to suggest that anterior pituitary endo-oligopeptidase B may be related to the control gonadotrophin secretion in female rats.
KW - Endo-oligopeptidase B
KW - LH-RH degrading enzyme
KW - Proline-endopeptidase
KW - Sexual steroids
UR - http://www.scopus.com/inward/record.url?scp=0021738877&partnerID=8YFLogxK
U2 - 10.1016/0196-9781(84)90131-1
DO - 10.1016/0196-9781(84)90131-1
M3 - Artículo Científico
C2 - 6390358
AN - SCOPUS:0021738877
SN - 0196-9781
VL - 5
SP - 1017
EP - 1019
JO - Peptides
JF - Peptides
IS - 5
ER -