Abnormalities in Pituitary Thyroid Axis Function Tests in Patients with Paroxysmal Supraventricular Arrhythmias

1987 ◽  
Vol 19 (02) ◽  
pp. 71-75 ◽  
Author(s):  
F. Vermiglio ◽  
S. Benvenga ◽  
A. Granata ◽  
G. Sobbrio ◽  
C. Melluso ◽  
...  
Life ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 426
Author(s):  
Giuseppe Bellastella ◽  
Maria Ida Maiorino ◽  
Lorenzo Scappaticcio ◽  
Annamaria De Bellis ◽  
Silvia Mercadante ◽  
...  

Chronobiology is the scientific discipline which considers biological phenomena in relation to time, which assumes itself biological identity. Many physiological processes are cyclically regulated by intrinsic clocks and many pathological events show a circadian time-related occurrence. Even the pituitary–thyroid axis is under the control of a central clock, and the hormones of the pituitary–thyroid axis exhibit circadian, ultradian and circannual rhythmicity. This review, after describing briefly the essential principles of chronobiology, will be focused on the results of personal experiences and of other studies on this issue, paying particular attention to those regarding the thyroid implications, appearing in the literature as reviews, metanalyses, original and observational studies until 28 February 2021 and acquired from two databases (Scopus and PubMed). The first input to biological rhythms is given by a central clock located in the suprachiasmatic nucleus (SCN), which dictates the timing from its hypothalamic site to satellite clocks that contribute in a hierarchical way to regulate the physiological rhythmicity. Disruption of the rhythmic organization can favor the onset of important disorders, including thyroid diseases. Several studies on the interrelationship between thyroid function and circadian rhythmicity demonstrated that thyroid dysfunctions may affect negatively circadian organization, disrupting TSH rhythm. Conversely, alterations of clock machinery may cause important perturbations at the cellular level, which may favor thyroid dysfunctions and also cancer.


2021 ◽  
Vol 80 (3) ◽  
pp. 567-578 ◽  
Author(s):  
Rosaria Sciarrillo ◽  
Mariana Di Lorenzo ◽  
Salvatore Valiante ◽  
Luigi Rosati ◽  
Maria De Falco

Abstract Different environmental contaminants disturb the thyroid system at many levels. AlkylPhenols (APs), by-products of microbial degradation of AlkylPhenol Polyethoxylates (APEOs), constitute an important class of Endocrine Disrupting Chemicals (EDCs), the two most often used environmental APs being 4-nonylphenol (4-NP) and 4-tert-octylphenol (4-t-OP). The purpose of the present study was to investigate the effects on the thyroid gland of the bioindicator Podarcis siculus of OP alone and in combination with NP. We used radioimmunoassay to determine their effects on plasma 3,3′,5-triiodo-L-thyronine (T3), 3,3′,5,5′-L-thyroxine (T4), thyroid-stimulating hormone (TSH), and thyrotropin-releasing hormone (TRH) levels in adult male lizards. We also investigated the impacts of AP treatments on hepatic 5′ORD (type II) deiodinase and hepatic content of T3 and T4. After OP and OP + NP administration, TRH levels increased, whereas TSH, T3, and T4 levels decreased. Lizards treated with OP and OP + NP had a higher concentration of T3 in the liver and 5′ORD (type II) activity, whereas T4 concentrations were lower than that observed in the control group. Moreover, histological examination showed that the volume of the thyroid follicles became smaller in treated lizards suggesting that that thyroid follicular epithelial cells were not functionally active following treatment. This data collectively suggest a severe interference with hypothalamus–pituitary–thyroid axis and a systemic imbalance of thyroid hormones. Graphic Abstract


1976 ◽  
Vol 42 (6) ◽  
pp. 1179-1181 ◽  
Author(s):  
R. M. STEWART ◽  
S. HEMLI ◽  
G. H. DANIELS ◽  
E. H. KOLODNY ◽  
F. MALOOF

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