Chronic Effects of Mercury on Organisms:

Proteinemic shifts in experimental mercurialism


NOTE: These are notes are incomplete.
Please refer to the original for scientific research.

PROTEINEMIC SHIFTS IN EXPERIMENTAL MERCURIALISM Summary only Data of Sh. A. Galoyan (1959) indicates that under the effect of mercury, there is produced in experimental rats a disappearance of conditional reflex extinction. In the brain tissue there was blockage of 0.1 - 0.2% of all free SH- groups, when mercury is present in extremely small (0.0015 mg/g tissue) quantities. This data agrees with that of V. A. Shalimov (1956, 1960) possibly indicating that the brain retains mercury differently because the localization of SH- groups in the microstructure of the brain is by no means homogeneous. Materials of V. V. Portugalov and V. A. Yakovolev (1959) indicate that in the microstructure of various separate parts of the central nervous system (CNS) the number of thiol groups is not uniform. Thus, to observe the quantitative changes in sulfhydryl groups of brain tissue, arising under the influence of mercury, one must produce not only "summary" determinations of SH- groups in he total brain, but determine them in the separate microstructures. Here another analogy is appropriate. The mere accumulation of mercury in the brain tissue provides an inadequate neurological picture to indicate a toxic effect. M. Berlin's autoradiography method (1963, 1966) allows the selective determination of mercury in separate brain structures, greatly clarifying the problem. The accumulation of mercury in brain tissue is not as significant as in several other organs, but it is observed in parts of the brain in quantities equal to the massive depots in the body, particularly the liver. The selective "topography" of mercury distribution in CNS structures will determine the corresponding localization of primary reaction sites of mercury with free thiol groups. The effects of low mercury concentrations not only show up the intensity of the course of protein metabolism, but to a definite degree can alter the structure of the protein molecule. They form stable complex compounds of mercury ions and tissue proteins and block the functional groups of cell proteins. Low mercury concentrations affect a series of specific protein functions -- enzymatic, immunological and hormonal. According to V. A. Belitser, 1950, 1954; A. G. Pasynskiy, 1952, the activity of specific proteins is directly dependent on the presence on the surface of their molecules of special reactive centers, composed of molecules of specific reactive centers, composed of an aggregate of amino acids or separate groups. Changes in the chemical structure of the protein molecule, caused by the disorganization of these centers of mercury can decrease the specific activity of enzyme systems, immunity factors, hormones, etc. Shifts in specific protein activity in combination with depression of synthetic processes and the prevalence of destructive changes, illustrates the general resistance of the organism to various harmful agents. This is the basis for inquiries into the appearance of latent effects arising under the influence of small mercury concentrations using methods of immune reaction analyses and analysis of certain endocrine functions.