Stimulation of chick adrenal steroidogenesis by avian parathyroid hormone

1988 ◽  
Vol 116 (1) ◽  
pp. 91-95 ◽  
Author(s):  
J. Rosenberg ◽  
M. Pines ◽  
S. Hurwitz
Keyword(s):  
Parathyroid Hormone ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Steroid Hormone ◽  
Hormone Secretion ◽  
Peptide Hormone ◽  
Adrenocortical Cells ◽  
Dependent Protein Kinase ◽  
Dependent Protein ◽  
Stimulation Of

ABSTRACT Dispersed chick adrenocortical cells were incubated with avian parathyroid hormone (aPTH) or ACTH. Accumulation of cyclic AMP (cAMP), activity of cAMP-dependent protein kinase and the secretion of corticosterone and aldosterone, in response to these hormones, were measured. Accumulation of cAMP and activity of cAMP-dependent protein kinase were stimulated by both aPTH and ACTH as well as by cholera toxin. Cyclic AMP production followed a similar time-course when stimulated by either peptide hormone. Stimulation of steroid hormone secretion was detectable after 20 min of incubation with ACTH, but only after 40 min with aPTH. The maximal steroid hormone secretion by adrenocortical cells was similar when induced by either peptide hormone. The aPTH concentrations needed for half-maximal response of corticosterone and aldosterone secretion were higher than those for ACTH (2·5- and 2-fold respectively), but still within the physiological range. The 11β-hydroxylase inhibitor metyrapone inhibited the secretion of both corticosterone and aldosterone when induced by either aPTH or ACTH. The results suggest that aPTH is almost as potent as ACTH in stimulating the secretion of corticosterone and aldosterone from chick adrenocortical cells and utilizes a cAMP-dependent pathway similar to that of ACTH. J. Endocr. (1988) 116, 91–95

scholarly journals Parathyroid hormone induces rat interstitial collagenase mRNA through Ets-1 facilitated by cyclic AMP response element-binding protein and Ca(2+)/calmodulin-dependent protein kinase II in osteoblastic cells

2000 ◽  
Vol 25 (1) ◽  
pp. 73-84 ◽  
Author(s):  
CO Quinn ◽  
RA Rajakumar ◽  
OA Agapova
Keyword(s):  
Parathyroid Hormone ◽  
Protein Kinase ◽  
Cyclic Amp ◽  
Osteoblastic Cells ◽  
Dependent Protein Kinase ◽  
Response Element ◽  
Nuclear Factors ◽  
Dependent Protein ◽  
Cyclic Amp Response Element ◽  
Interstitial Collagenase

Parathyroid hormone (PTH), a powerful bone-resorbing agent, is capable of stimulating interstitial collagenase (MMP-13) mRNA production in osteoblastic cells. In this study, a PEA3 consensus binding sequence (-80; AGGAAGT) in addition to a 'TRE-like' sequence (-89; CGACTCA) in the 5' upstream regulatory region of the rat MMP-13 gene were examined. In response to PTH, there was a time-dependent increase in binding of nuclear factors to an oligonucleotide containing the PEA3 region (-95 to -71). This increase in binding was first observed at 0.5 h, peaked at 4 h (7. 6-fold) then returned to basal levels by 24 h. Mutagenesis of the PEA3 site in a chloramphenicol acetyl transferase (CAT) construct containing 5' upstream regulatory sequence of the rat MMP-13 gene significantly decreased activation by PTH. PTH-mediated binding of nuclear factors to an oligonucleotide containing the mutant PEA3 sequence was decreased as compared with the wild type. Mutation or deletion of the TRE-like sequence affected basal as well as PTH-mediated induction of corresponding CAT constructs. Treatment with KN93, a Ca(2+)/calmodulin-dependent protein kinase II specific inhibitor, greatly reduced the amount of protein binding to the PEA3 region in response to PTH which correlated to a notable decrease in the amount of MMP-13 mRNA produced in response to PTH. Antibodies against Ets-1, cyclic AMP response element (CREB)-binding protein (CBP) and CREB were capable of supershifting proteins binding to the oligonucleotide containing the PEA3 region. These data suggest a possible co-operative interaction of factors binding to the PEA3 and TRE-like sequences and provide the first indication of a role for a calcium-mediated pathway in the PTH induction of MMP-13 mRNA in osteoblastic cells.

Effects of isoproterenol on cylic-AMP metabolism in rat ventral prostate

1976 ◽  
Vol 54 (3) ◽  
pp. 327-335 ◽  
Author(s):  
B. K. Tsang ◽  
R. L. Singhal
Keyword(s):  
Protein Kinase ◽  
Cyclic Amp ◽  
Adenylate Cyclase ◽  
Kinase Activity ◽  
Activity Ratio ◽  
Ventral Prostate ◽  
Adrenergic Stimulation ◽  
Dependent Protein Kinase ◽  
Dependent Protein ◽  
Stimulation Of

β-Adrenergic stimulation of the ventral prostate cyclic-AMP system was investigated by examining the influence of isoproterenol on endogenous cyclic-AMP levels as well as on the activities of adenylate cyclase (EC 4.6.1.1) and cyclic-AMP-dependent and independent protein kinases (EC 2.7.1.37). Administration of isoproterenol (1 mg/kg, ip) resulted in rapid elevation of adenylate cyclase activity (119%) and cyclic-AMP levels (593%). The observed isoproterenol-stimulated changes in cyclic-AMP metabolism of the ventral prostate were time-dependent and maximal stimulation was seen 5 min after treatment with this β-adrenergic agonist. The increases in prostatic adenylate cyclase and cyclic-AMP also were related to the dose of isoproterenol administered and maximal enhancement of these parameters was seen with 1 mg/kg dose of the agonist. Whereas pretreatment of rats with propranolol (3 mg/kg, ip) partially reversed these alterations, administration of an α-adrenergic antagonist, phentolamine, even at a dose of 5 mg/kg, failed to elicit any appreciable effect. Stimulation of prostatic soluble protein kinase by isoproterenol was associated with a decrease (33%) in the activity of the cyclic-AMP-dependent protein kinase with a concomitant increase (25%) in that of the independent enzyme. Whereas the ability of the enzyme to bind cyclic-[3H] AMP in vitro was decreased (54%) following isoproterenol treatment, the protein kinase activity ratio (−cyclic-AMP/+cyclic-AMP) was significantly elevated from 0.51 ± 0.05 to 0.95 ± 0.08. Although propranolol alone had little or no effect on these parameters, it inhibited partially the isoproterenol-induced alterations in cyclic-AMP-dependent protein kinase and the cyclic-AMP binding capacity. Treatment with propranolol also blocked the increases in the kinase activity ratio and in the activity of cyclic-AMP-independent enzyme seen with isoproterenol. Data suggest that the concentration of ventral prostate cyclic-AMP as well as the activities of adenylate cyclase and cyclic-AMP-dependent and independent form of protein kinases are subject to modulation by β-adrenergic stimulation.

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