[Effect of chronic exposure to nitrogen dioxide on biogenic amine levels in the brain of guinea pigs]. / Wplyw przewleklej ekspozycji dwutlenku azotu na zawartosc amin biogennych w mózgu swinek morskich.

The experiment was carried out on male guinea pigs exposed to NO2 at a constant concentration of 0.1 ppm 24 h daily for 1, 2.5 and 6 months, or NO2 concentration was increased to 0.5 ppm twice daily, between 7:00 and 8:00 AM and 4:00 and 5:00 PM. After the exposure to NO2 was over the animals were killed by decapitation. The cranium was opened and the brain removed, and afterwards at 0 degrees C the left hemisphere was dissected into discrete areas which were then frozen on dry ice and weighed. The tissues were kept for 2-3 days at -20 degrees C, and afterwards the content of noradrenaline, 5-hydroxytryptamine and 5-hydroxyindole-acetic acid was estimated spectrofluorometrically in examined parts of the brain (thalamus--hypothalamus pons + medulla oblongata hippocampus, cortex frontalis). It was shown that the applied NO2 concentrations brought about slight and nonspecific alterations in the content of the investigated amines in guinea pigs' brain.

Hypotensive action of prolactin in rats with spontaneous hypertension.

Rats (SHR) weighing 240 +/- 10 g with spontaneous hypertension were given intraperitoneally porcine prolactin in doses from 0.2 to 2000 micrograms/kg of body weight. The systolic pressure was measured before hormone administration and 2 hours after it. It was found that prolactin in doses of 200 to 2000 micrograms/kg caused a decrease of the systolic pressure by 22%. The dose of 20 micrograms/kg decreased this pressure by 9% and the dose of 0.2 microgram/kg by 7.9%.

Studies on the influence of combustion exhaust gases and the products of their reaction with ammonia on the living organism. I. The influence on DNA, RNA and soluble proteins in the liver of guinea pig.

The paper presents the behaviour of DNA, RNA and soluble proteins in whole homogenate as well as the nuclear, mitochondrial and postmitochondrial liver fractions in guinea pigs exposed to combustion exhaust gases and the products of their reaction with ammonia. A decrease of RNA level was found in the liver of animals exposed to combustion exhaust gases together with a decrease of soluble proteins in all the studied fractions. On the other hand, in the group of animals subjected to the action of neutralization products of combustion gases by ammonia, the studied components were increased. This increase may be the result of the simultaneous action of industrial noise.

Studies on the influence of combustion exhaust gases and the products of their reaction with ammonia on the living organism. II. The influence on aspartate aminotransferase (AspAT) and alanine aminotransferase (AiAt) activities in the liver of guinea pig.

The behaviour of aspartate aminotransferase (AspAT) an alanine aminotransferase (AIAT) in the whole homogenate and subcellular liver fractions of guinea pigs exposed to combustion exhaust gases and the neutralization products of these gases is presented in this paper. In the liver of animals exposed to the chronic action of combustion exhaust gases a decrease of both enzyme activities in the whole homogenate as well as in the subcellular fractions could be noted. Statistically significant changes are shown by AspAT. In the group of animals subjected to the action of neutralization products an increase of AIAT activity was observed. The activity of AspAT still shows a decrease, but less distinct in comparison with group I. An exception here is the mitochondrial fraction in which the AspAT activity is distinctly increased.

Studies on the effect of long-term exposure to nitrogen dioxide on serum and liver proteins level and enzyme activity in guinea pigs.

Forty male guinea pigs were exposed to nitrogen dioxide in a concentration of 2 mg/m3, 8 hours daily for a period of 180 days. Forty male animals were used as a control group. The following changes were found in intoxicated animals: the decrease of total protein and seromucoid concentration in blood serum and the decrease of total protein, perchloric acid-soluble proteins, protein-bound hexosamines and sialic acids content, in liver tissue. Electrophoretic examination of the serum proteins showed the increase of alpha 1- and beta 2-globulins and the decrease of albumin concentration. Changes in the level of glycoproteins fractions and protein-bound carbohydrates in blood serum were described also. Estimation of enzymes activity showed the decrease of alanine and aspartate transaminase activity in blood serum caused by the strong decrease of the cytoplasmic fraction of these enzymes. However the simultaneous increase of the mitochondrial fraction of transaminases activity was observed. The decrease of the activity of choline esterase was found also. Similar changes of enzymes activity were found in liver tissue. Histopathological studies were done for the further clearing the influenze of nitrogen dioxide on serum and liver proteins concentration and enzymes activity. It was found that after long-term exposure to nitrogen dioxide the destruction processes may be observed in the liver. The possible mechanism of the nitrogen dioxide-induced damage of protein metabolism is discussed.