| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Endocrinology, Vol 131, 2653-2658, Copyright © 1992 by Endocrine Society
ARTICLES |
FE Carr, HG Fein, CU Fisher, MW Wessendorf and RC Smallridge
Department of Clinical Investigation, Walter Reed Army Medical Center, Washington, D.C. 20307.
TRH is synthesized as a precursor peptide containing five copies of the sequence Gln-His-Pro-Gly, QHPG, flanked by paired basic amino acids, and linked by other peptides. We tested one cryptic peptide, PPT (160- 169, SFPWMESDVT), as a possible physiological regulator of pituitary activity in vivo. Male rats were cannulated (jugular) and received a single dose of either PPT or TRH (10(-8)-10(-6) M). PPT caused no consistent effects on either TSH or PRL secretion, while TRH stimulated the secretion of both hormones. However, PPT stimulated a dose- dependent increase in both pituitary TSH beta and PRL mRNA content at 240 min similar to TRH. In primary cultures of rat pituitaries, PPT stimulated a maximum 4-fold increase in TSH beta mRNA and a 2-fold increase in PRL mRNA in 4 h, while TRH increased both TSH beta and PRL mRNA approximately 3-fold. Again, PPT had no significant effect on TSH or PRL secretion into the medium. Thus, PPT appears to be a physiological regulator of both TSH and PRL synthesis, but, unlike TRH, does not act as a secretagogue.
This article has been cited by other articles:
![]() |
K. Valentijn, F. Vandenbulcke, E. Piek, J.-C. Beauvillain, and H. Vaudry Distribution, Cellular Localization, and Ontogeny of Preprothyrotropin-Releasing Hormone-(160-169) (Ps4)-Binding Sites in the Rat Pituitary Endocrinology, March 1, 1998; 139(3): 1306 - 1313. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Yamada, Y. Saga, N. Shibusawa, J. Hirato, M. Murakami, T. Iwasaki, K. Hashimoto, T. Satoh, K. Wakabayashi, M. M. Taketo, et al. Tertiary hypothyroidism and hyperglycemia in mice with targeted disruption of the thyrotropin-releasing hormone gene PNAS, September 30, 1997; 94(20): 10862 - 10867. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |