ABSTRACT
It was shown that the experimental hypofunction of thyroid, induced by thyroidectomy and strong gamma-irradiation with a dose of 1 Gy lead to disturbance of function and structure of membranes of sarcoplasmic reticulum of myocites in rats. Introduction in vivo of L-thyroxine rose functional capacity of membranes with insignificaut changes in their lipid bilayer.
Subject(s)
Hormones/metabolism , Intracellular Membranes/radiation effects , Muscle Cells/radiation effects , Sarcoplasmic Reticulum/radiation effects , Animals , Calcium/metabolism , Dose-Response Relationship, Radiation , Fluorescence , Gamma Rays , Intracellular Membranes/drug effects , Intracellular Membranes/metabolism , Lipid Bilayers/radiation effects , Male , Muscle Cells/drug effects , Muscle Cells/metabolism , Rats , Sarcoplasmic Reticulum/drug effects , Sarcoplasmic Reticulum/metabolism , Thyroid Gland/metabolism , Thyroid Gland/surgery , Thyroidectomy , Thyroxine/pharmacology , Tryptophan/chemistryABSTRACT
Thyroidectomy or administration of high activities (> 1.1 Mbq) of 131I to rats causes initial decrease in blood concentration of thyroid hormones which returns to the normal level. Administration of lower doses (< 1.1 Mbq) of radioactive iodine or external radiation (1, 3, 6 Gr) did not cause similar changes. Data obtained that: 1) thyroid gland is relatively radioresistant organ with high reparative function after surgical or radioactive damage; 2) alterations of thyroid status after the external radiation are not related to a direct action of radiation on the thyroid gland.
Subject(s)
Thyroid Gland/radiation effects , Thyroidectomy , Thyroxine/blood , Triiodothyronine/blood , Whole-Body Irradiation , Animals , Dose-Response Relationship, Radiation , Iodine Radioisotopes , RatsABSTRACT
The alterations of amount of thyroid hormones have the characteristic dynamics that manifest itself by initial reduction with following partial or complete restoration of T3 and T4 concentration in rat blood after surgical or radioactive injuries of thyroid gland. Through presence of threshold of several dozens Gy for early dose-dependent hypothyroidism, the thyroid gland seems to be relatively radioresistant organ. Thyroid hormones concentration in blood has restored to normal level after experimental injuries which shows high restoration potential of thyroid gland function.
