Thyroid gland substrates

When TSH contacts its receptor-sites located throughout the thyroid gland a series of enzymic reactions occur using tyrosine and iodine as substrates or raw materials to produce and/or release L-Thyroxine (T-4). This is then released into the vascular system so it can circulate. It should be noted that T-4 is an active form of thyroid hormone. 

Guggulsterones Z and E seem to have the greatest effect upon stimulation of thyroid hormone, though other substrates of the herb commiphora mukul may effect different metabolic factors as well. Thus far, research suggests this is a result of guggulsterones Z E stimulation of TSH (Thyroid-Stimulating-Hormone) production. This results in an increase in Thyroid gland T-4 production and subsequent liver conversion to the more active T-3 hormone. 

Iodide, the main substrate used in the synthesis of thyroid hormone, exerts a negative control on the activity and growth of the thyroid gland. 

The biochemical mechanisms by which cAMP-dependent phosphorylation leads to enhanced IR-PTH release remain to be determined. It is of interest, however, that isoproterenol activates phosphorylation of proteins of similar molecular weight in the rat parotid gland (22), while glucagon stimulates phosphorylation of a protein of molecular weight 19,000 in calcitonin-secreting cultured cells from a medullary carcinoma of the rat thyroid (22) It is conceivable that in all three tissues, activation of exocytosis results from a cAMP-dependent phosphorylation of a critical cellular substrate. 

Iodide therapy (usually saturated solution of potassium iodide) is useful in reducing thyroid hormone release and in decreasing the vascularity of the gland prior to surgery. However, escape from the inhibitory effect of iodide often occurs in Graves disease, and the increased iodine substrate made available by the therapy may actually accentuate the disease. 

The lactating mammary gland concentrates iodide from blood into milk, and thereby defivers necessary substrate for neonatal and infant thyroid hormone production. NIS in the mammary gland is identical to thyroidal... 

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