Download PDF
Horm Metab Res 1986; 18(9): 625-629
DOI: 10.1055/s-2007-1012390
Clinical

© Georg Thieme Verlag, Stuttgart · New York

Prostacyclin Stimulation of Adenylate Cyclase Activity in Human Thyroid Membranes

K. Kasai, M. Hiraiwa, Y. Suzuki, N. Banba, T. Emoto, T. Nakamura, S.-I. Shimoda
  • Department of Endocrinology, Internal Medicine, Dokkyo University School of Medicine, Mibu, Tochigi, Japan
Further Information

Publication History

1984

1985

Publication Date:
14 March 2008 (online)

Also available at
  PDF Download  Permissions and Reprints

Summary

Effect of prostacyclin (PGI2) on adenylate cyclase activity in human thyroid membranes was examined. PGI2 caused a dose- and time-dependent production of cyclic AMP (cAMP) with high potency. When GTP was added in concentrations up to 100 uM, the activation of adenylate cyclase by PGI2 was increased. In the assay medium containing 3 mM ATP, 10 uM GTP and nucleotide regenerating system, the replacement of Mg2+ by increasing concentrations of Mn2+ caused a progressive loss of PGI2 as well as TSH-stimulated adenylate cyclase activities, while high concentrations of Mg2+ (12 or 18 mM) slightly suppressed the activity stimulated by either PGI2 or TSH. Both agents had an additive effect on the stimulation of adenylate cyclase activity in the presence of either 6 mM Mg2+ or 6 mM Mn2+. Gamma-globulin fraction containing non-stimulatory TSH receptor antibody which was prepared from a patient with chronic thyroiditis, suppressed only TSH- but not PGI2-stimulation of the adenylate cyclase activity. These results suggest that PGI2 can stimulate the adenylate cyclase activity in human thyroid tissue, and that PGI2-stimulation may be mediated by the different system from TSH-dependent one.

Key-Words

Human Thyroid Membranes - Prostacyclin - TSH - Adenylate Cyclase

      >