Serum thyroxine and thyroid-stimulating hormone concentration in hyperthyroid cats that develop azotaemia after radioiodine therapy

2017 ◽  
Vol 58 (9) ◽  
pp. 519-530 ◽  
Author(s):  
M. E. Peterson ◽  
R. Nichols ◽  
M. Rishniw
1972 ◽  
Vol 55 (3) ◽  
pp. 479-487 ◽  
Author(s):  
D. EMRICH ◽  
A. von zur MÜHLEN ◽  
J. LINDNER ◽  
H. D. ZIMMERMANN ◽  
R. BECKMANN

SUMMARY In order to investigate the influence of thyroid-stimulating hormone (TSH) on the ratio of newly synthesized thyroxine( T4):tri-iodothyronine (T3), hemithyroidectomy was performed on rats maintained on an iodinerich diet. One and two weeks after the operation the concentration of TSH increased in the plasma. As a result, the weight of the residual lobes and their thyroidal uptake of 131I/mg increased and significant histological signs of increased function in the remaining lobes were observed. The most prominent effect was a significant alteration of the ratio of newly synthesized T4:T3 in favour of T3, both in the thyroid and plasma. Four weeks after the operation, when the residual lobes weighed 57% more than those in the controls, the alterations decreased or returned to normal. The total hormone concentration in the plasma (measured as protein-bound 127I) and the oxygen consumption of the animals remained unchanged during the entire study. These findings support the hypothesis that alteration of the production and secretion ratio of T4:T3 induced by TSH might act as another regulatory factor, if a hormone deficiency originates in the peripheral cells. The results show also that changes of the T4:T3 ratio induced by TSH occur in animals on an iodine-rich diet.


2014 ◽  
Vol 13 (3) ◽  
pp. 93-96
Author(s):  
Shaheda Ahmed ◽  
A S M Towhidul Alam

Objective: To review current concepts in the management of subclinical hypothyroidism (SCH) in patients with non-specific symptoms.Data sources: A review of articles reported on overt hypothyroidism and subclinical hypothyroidism. Summary of review: In a patient with primary overt hypothyroidism, management is usually straightforward: treatment with thyroxine should be offered to anyone with characteristic clinical features, a raised serum thyroid stimulating hormone (TSH) concentration and a low serum thyroxine (T4) concentration. More difficult is the management of a patient with subclinical hypothyroidism (SCH), in whom serum TSH is slightly raised (5-20 mIU/L) but T3, T4 levels are normal, and who is either asymptomatic or has only non-specific symptoms. Left untreated, some of these patients will eventually develop overt hypothyroidism. This review will address the use of thyroxine in patients with subclinical hypothyroidism.DOI: http://dx.doi.org/10.3329/cmoshmcj.v13i3.21045 


Sign in / Sign up

Export Citation Format

Share Document