CHANGES IN THE NUMBER OF NEURONS, ASTROCYTES AND MICROGLIA IN THE BRAIN AFTER ISCHEMIC STROKE ASSESSED BY IMMUNOHISTOCHEMISTRY AND IMMUNOBLOTTING.

It is known that the mechanisms of damage in the brain after stroke are regulated by combination of several types of cells, primarily of neurons, astrocytes, endothelium and microglia. Ischemic exposure disrupts the balance in the cellular composition of the brain; in the lesion, cells die by necrosis while in tissue surrounding ischemic zone the delayed induction of apoptosis occurs, and namely the ratio of death of different cells determines the clinical outcome of the disease. Thus, the assessment of death of various cell types of the neurovascular unit is an important part of fundamental studies of the mechanisms of brain damage and pre-clinical studies of potential neuroprotective drugs. In this line, we have conducted a comparative study of the two most often used methods: immunohistochemical staining of brain sections, allowing to determine the number and localization of specific cells in the tissue among other types of cells, and immunoblotting that detects specific proteins in the tissue homogenate. We have found that, depending on the type of cells, changes in their number and composition after stroke can be diffuse or localized, which imposes restrictions on the use of any method of estimation of the number of cells in brain tissue. In general, the most preferable is the use of immunohistochemistry, however, with certain limitations, immunoblotting can be used in estimating amounts of astroglia and microglia.