**7. Future research direction**

Recent information regarding nongenomic mechanism of thyroid hormone action in various tissue types including mammalian CNS is interesting. These studies are diligently engaged in decoding the molecular consequences of thyroid hormone action from the specific gene expression to the nongenomic rapid actions of the hormone. Open-minded investigators are desperately searching for the truth and the relationship of thyroid hormone action explicated through its classical well-known doctrine which is mediated via activation of specific nuclear receptors to the newly emerging idea of rapid nongenomic actions of the hormone and an association to enlighten the both. In particular, adult mammalian brain are of best curiosity since clinical observations of numerous thyroid dysfunction related neuropsychological disorders produced during mature conditions in humans can be corrected with the adjustment of the thyroid hormone levels. However the mechanism of action is lacking. Nongenomic rapid events mediated by thyroid hormones could have connection to the long-term genomic actions. Deciphering the nongenomic molecular mechanism of action of thyroid hormones has future prospects to study its importance regulating higher mental functions in humans. This fundamental knowledge could be the basis to find novel strategies to treat adult-onset thyroid dysfunctions including neuropsychological diseases many of which are precisely controlled by demarcated cellular fine-tuning of the protein phosphorylation mechanisms related to neuronal signal transmission.

"Quo Vadis?" Deciphering the Code of Nongenomic Action of Thyroid Hormones in Mature Mammalian Brain 31

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