Related Experiment Video
Updated: Feb 11, 2026

Evaluation of Left Ventricular Structure and Function using 3D Echocardiography
Published on: October 28, 2020
The Change of Left Ventricular Function in Rats with Subclinical Hypothyroid and the Effects of Thyroxine Replacement
Xuedi Chen1,2, Cuixia Gao3, Ningning Gong1,4
1Department of Endocrinology, Gansu Provincial Hospital, Lanzhou, China.
Objective:
The main purpose of this study was to explore the relationships between serca2a, Ryr2, adipokines, and the left ventricular function in the subclinical hypothyroidism with different TSH levels and to determine the impact of L-T4 treatment on these indexes.
Methods:
Sixty-five male Wistar rats were randomly divided into five groups: control group; sHT A, B, and C group; and sHT + T4 group. The sHT rats were induced by methimazole (MMI), and the sHT + T4 rats were administered with L-T4 treatment after 8 weeks of MMI administration. Serum TT4, TSH, APN, chemerin, and TNF-α were detected by radioimmunoassay kits and ELISA kits; left ventricular function was measured by PowerLab system via subclavian artery catheter. The expression of Serca2a, Ryr2, APN, chemerin, and TNF-α were detected by RT-PCR, Western blot, and immunohistochemistry.
Results:
The sHT groups had significantly higher TSH, chemerin, and TNF-α and lower Serca2a, Ryr2, and APN. The left ventricular pressure and heart rate in sHT groups were significantly lower in control and sHT + T4 group. Histopathological examination revealed the pathological changes in the sHT rats' heart. L-T4 administration reduced TSH level and improved left ventricular function.
Conclusions:
TSH can impair left ventricular function by regulating several factors, and L-T4 treatment ameliorates it in sHT rats.
More Related Videos
Related Concept Videos
Standard Entropy Change for a Reaction
Global Climate Change
Rates of Change
Work Done During Volume Change
Consider a gas confined to a cylinder fitted with a movable piston at one end. If the gas expands from volume V1 to volume V2, it exerts a force on the piston, such that the piston moves by a distance dr.
The work done by the gas on the piston can be expressed as
Le Chatelier's Principle: Changing Temperature
To understand this phenomenon, consider the elementary reaction:
Continuous Renal Replacement Therapy

