Endocrine Abstracts

Scientific literature contains data on HCO₃⁻-activated and Mg²⁺-stimulated ATPase detected in various tissues of vertebrate animals, specifically in the pancreas mucus, liver, kidneys, erythrocytes, diaphragm and various structures in the brain. It has been discovered that maximum enzymatic activity is characteristic to secretory tissues.

The nature and function of this ferment has not been fully discovered, although several assumptions do exist. One of them maintains that HCO₃⁻-ATPase is an active participant in the regulation of intracellular pH.

This research has aimed at the study of human thyroid gland HCO₃⁻-ATPase and changes in its activity under various pathologies (gland adenoma, carcinoma and diffusive-toxic goiter).

In order to achieve the goals set before the research we have studied distribution of enzymatic activity in the mitochondrial, nuclear fractions and those taken from endoplasmic reticulum and plasma membranes from healthy and affected human thyroid tissues, for which a relevant permit was pre-obtained from the Ministry of Health. The received data have shown an especially high enzymatic activity in the mitochondrial and plasma membrane fractions. Alongside we have observed radical changes in HCO₃⁻-ATPase activity under various gland pathologies, such as adenoma, carcinoma and diffusive-toxic goiter.

In order to establish the nature of HCO₃⁻-ATPase activity changes we have studied kinetic properties of the enzyme, such as V_max and K_m in healthy and sick gland tissues and determined kinetic parameters of the enzyme.

Based on the available data we have assumed that formation of various thyroid pathologies is accompanied by changes in HCO₃⁻-ATPase activity, which could possibly lead to the gland-related diseases.