TY - JOUR
T1 - Effects of phorbol esters on metabolic variables in the thyroid
AU - Yoshimura, Yoshiyuki
AU - Dekker, Andrew
AU - Ferdows, Mehdi
AU - Rani, C. S.Sheela
AU - Field, James B.
PY - 1986/11
Y1 - 1986/11
N2 - Since 12-O-tetradecanoyl-phorbol-13-acetate (TPA) reproduced some of the effects of TSH on phosphorylation of polypeptides in the thyroid, its effects on several thyroid metabolic variables were investigated. Like TSH, TPA stimulated glucose oxidation, iodide organification, and 32P incorporation into phospholipids in thyroid slices. However, in contrast to TSH, it did not augment cAMP accumulation. An inactive phorbol ester, 4α-phorbol, did not reproduce any of the effects of TPA. An initial incubation of thyroid slices with TPA decreased the stimulation of cAMP, glucose oxidation, and colloid droplet formation induced by TSH. However, an initial incubation with TPA did not modify the subsequent stimulation of glucose oxidation induced by (Bu)2 cAMP. TPA potentiated the ability of TSH to densensitize the adenylate cyclase system. Although both TPA and TSH increased 32P incorporation into phospholipids, the patterns were different when individual phps-pholipids were examined. These results indicate another regulatory mechanism for thyroid cell functions independent of cAMP.
AB - Since 12-O-tetradecanoyl-phorbol-13-acetate (TPA) reproduced some of the effects of TSH on phosphorylation of polypeptides in the thyroid, its effects on several thyroid metabolic variables were investigated. Like TSH, TPA stimulated glucose oxidation, iodide organification, and 32P incorporation into phospholipids in thyroid slices. However, in contrast to TSH, it did not augment cAMP accumulation. An inactive phorbol ester, 4α-phorbol, did not reproduce any of the effects of TPA. An initial incubation of thyroid slices with TPA decreased the stimulation of cAMP, glucose oxidation, and colloid droplet formation induced by TSH. However, an initial incubation with TPA did not modify the subsequent stimulation of glucose oxidation induced by (Bu)2 cAMP. TPA potentiated the ability of TSH to densensitize the adenylate cyclase system. Although both TPA and TSH increased 32P incorporation into phospholipids, the patterns were different when individual phps-pholipids were examined. These results indicate another regulatory mechanism for thyroid cell functions independent of cAMP.
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U2 - 10.1210/endo-119-5-2018
DO - 10.1210/endo-119-5-2018
M3 - Article
C2 - 3021433
AN - SCOPUS:0023013742
VL - 119
SP - 2018
EP - 2024
JO - Endocrinology
JF - Endocrinology
SN - 0013-7227
IS - 5
ER -