An approach to investigation of the changing pattern of plasma cyclic nucleotides and their correlation with thyroid hormone in hyperthyroid patients before and after¹³¹I treatment

Abstract

Levels of thyroid hormones (T₃,T₄) in serum and cyclic adenosine 3′, 5′-monophosphate (cAMP) and cyclic guanosine 3′, 5′-monophosphate (cGMP) in plasma were successively determined in 77 patients with hyperthyroidism before and 1, 2, 3, 6 months after¹³¹iodine (¹³¹I) treatment. Before treatment, the levels of total serum T₃, T₄ and plasma cAMP of all of the patients were higher than normal, while the level of plasma cGMP was lower than normal (P<0.0l). The patients were divided into 3 groups: A, B, C, according to the clinical features and serum levels of T₃, T₄ 3–6 months after treatment. Group A (18 patients) clinically showed no improvement, T₃, T₄ still remained higher than normal and cAMP, cGMP revealed no significant change in comparison with the pretreatment state. Group B (45 patients) clinically showed marked improvement, their thyroid toxic symptoms practically subsided, T₃, T₄ gradually turned to normal and concentration of cAMP and cGMP subsequently reached normal level. Group C (14 patients) presented temporary hypothyroidic features; their level of T₃, T₄ fell below the normal range, while the concentration of plasma cAMP and cGMP approached the level contrary to the state before treatment. Since the change of T₃ and T₄ occurred synchronously, the question of whether T₃ or T₄ exerted an influence on plasma cyclic nucleotides concentration and the interrelationship between thyroid hormones and cyclic nucleotides as well as the significance of plasma cAMP and cGMP in pathogenesis and therapy of hyperthyroidism remains to be further elucidated.

Keywords

hyperthyroidism / T₃ / T₄ / cAMP / cGMP / quality control / transient hypothyroidism / dynamic changes

References

[1] GoldbergND, et al.. Biologic regulation through opposing influences of cAMP and cGMP: The Yin Yang hypothesis. Adv Cyclic Nucleotide Res, 1974, 5: 307-307

[2] 11, 1978

[3] LinT. Plasma cyclic nucleotide levels in hyperthyroidism. Acta Endocrinol, 1979, 90: 62-62

[4] KarlbergBE, et al.. Cyclic AMP concentration in plasma, adipose tissue and skeletal muscle in normal subjects and in patients with hyper- and hypothyroidism. J Clin Endocrinol Metab, 1974, 39: 96-96

[5] HardmanJG, et al.. Effects of some hormonal and other factors on the excretion of guanosine 3′, 5′-monophosphate and adenosine 3′, 5′-monophosphate in rat urine. J Biochem, 1969, 244: 6345-6345

[6] Fernandez-PolJA, et al.. Alterations in cyclic nucleotides in dogs after T₃. Acta Endocrinol, 1975, 79: 66-66

[7] (7): 21, 1979

[8] WaryHL, et al.. Effect of 3,5,3′-triiodothyronine and 3,3′,5′-triiodothyronine administration on serum tri-, di-, and monoiodothyronines and plasma cyclic nucleotides in sheep. Endocrinology, 1980, 107(1): 130-130

[9] CaterDJ, et al.. The effect of treatment of hyper and hypo thyroidism on urinary excretion of cyclic adenosine 3′, 5′-monophosphate. Acta Endocrinol, 1977, 84: 547-547

[10] CaterDJ, et al.. UcAMP excretion in thyroid disease. Clin Sci Mol Med, 1974, 47: 19-19

[11] cAMP (2): 153, 1981

[12] MaedaM, et al.. Changes in serum triiodothyronine, thyroxine, and thyrotropin during treatment with thyroxine in severe primary hypothyroidism. J Clin Endocrinol Metab, 1976, 43: 10-10

[13] ChopraIJ, et al.. Thyroxine: Just a prohormone or a hormone too?. J Clin Endocrinol Metab, 1973, 36: 1050-1050