Biomedical subjects

A Pogorelov

Publications and source records attributed to A Pogorelov.

3 recordsLinked to original sources

PubMed1997

Assay of acetylcholinesterase activity and elemental composition in brain compartments by electron probe microanalysis.

Using histochemical techniques the distribution of acetylcholinesterase (AChE) activity in rat brain has been well established. These assays are based on the precipitation of a specific deposit containing copper-ferricyanide. The amount of locally deposited product is proportional to the AChE activity in the examined area of the section. Thus, the amounts of copper or (and) iron as the deposited histochemical labels mark the distribution and magnitude of the enzyme activity. The present protocol describes an approach to obtain by electron probe microanalysis (EPMA) a map of copper deposited in different brain regions via AChE histochemistry. EPMA allows a wide range of chemical elements to be analyzed. Thus, together with the determination of the copper concentration, elemental contents (Na, Cl, K and Ca) are measured as the specific environment for local AChE activity.

Acetylcholinesterase↗

PubMed1994

Quantitative biological electron probe microanalysis with a wavelength dispersive spectrometer.

This paper describes the details of quantitative electron probe microanalysis (EPMA) performed with a wavelength dispersive spectrometer (WDS). EPMA was carried out on the giant neuron of a fresh frozen ganglion from the snail Lymnaea stagnalis. The freeze-dried cryosections were compared with sections of freeze-dried, embedded tissue. It was found, that in the ganglion there are two kinds of neurons with a different chlorine concentration of 11 mmole/liter and 32 mmole/liter. Isolated neurons in culture were shown to differ in elemental composition from those in the ganglion tissue.

Animals↗

PubMed1991

Study of potassium deficiency in cardiac muscle: quantitative X-ray microanalysis and cryotechniques.

An imbalance of potassium in cardiac muscle causes an alteration of heart function. The distribution and concentration of potassium in rat papillary heart muscle was studied using cryofixation and X-ray microanalysis. Freeze-dried cryosections and sections of freeze-dried, embedded tissue were analysed. Bulk frozen specimens were freeze-dried either in a vacuum or by a new technique using liquid propane as a cryodehydration medium. These two methods of freeze-drying were tested for elemental retention in other specimens, with comparable results. A potassium concentration of 120 mmol/l was measured in normal myocytes of cardiac papillary muscle compared to 80 mmol/l in myocytes of animals stressed by a temperature of 45 degrees C for 1 h. The presumed physiological significance of the findings is discussed.

Animals↗