Effect of cultivation temperature on blast transformation of lymphocytes from people of different ages

The effect of the cultivation temperature on blast transformation of lymphocytes from persons aged 20–35 and 90–102 years induced by phytohemagglutinin was studied. Cultivation at 39°C was found to increase, but at 41°C to reduce sharply the index of blast transformation compared with the control (37°C). The effect of cultivation temperature on the blast-transformation process has certain features which depend on the donors' age.Institute of Gerontology, Academy of Medical Sciences of the USSR, Kiev. (Presented by Academician of the Academy of Medical Sciences of the USSR D. F. Chebotarev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 470–472, April, 1977.     

Effect of a suboptimal temperature on the mitotic regime

Keeping Chinese hamster cells for 2 h at a suboptimal temperature (21°C) leads to a fall in the mitotic index and delay of division at the metaphase state. Cooling cause a sharp increase in the number of pathological mitoses, mainly as a result of injury to the mitotic apparatus: C mitoses and dispersion of the chromosomes in metaphase. After transfer of the cells to optimal temperature conditions the mitotic regime is completely restored after 1 h, but at this time the number of pathological mitoses is still appreciably greater than in the control.Laboratory of Cytology, Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 216–218, February, 1977.     

Fluorimetric determination of histamine and serotonin in mast cells of normal and germfree rats treated with reserpine and cyclic AMP

The content of histamine (by the reaction with orthophthalic aldehyde) and serotonin (by Falk's reaction) in mesenteric mast cells of normal and germfree rats was determined microspectrometrically. Reserpine (10 mg/kg, intramuscularly) was shown not to change the histamine content, whereas the serotonin content was reduced by 50%. Injection of cyclic AMP (3.5 mg/kg, intraperitoneally) caused the serotonin content to be increased by 80% and the histamine content by 280–320%.Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR. Research Laboratory of Experimental Biological Models, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny. Vol. 83, No. 2, pp. 175–177, February, 1977.     

Effect of an atherogenic diet on age differences in cholesterol biosynthesis in the rat liver

After intraperitoneal injection of radioactive sodium acetate into rats of two age groups (6–8 and 28–32 months) the dynamics of cholesterol biosynthesis in the liver was observed to be slower in the older animals. The specific liver cholesterol activity of the older rats was lower at the maximum of uptake of the label than in the younger rats. An atherogenic diet for 20 days (0.25 g cholesterol/100 g body weight) led to an increase in the total cholesterol content but to inhibition of its biosynthesis in the liver, and this effect was most marked in the younger rats. Continued administration of cholesterol depressed its biosynthesis still more, especially in the older animals.Laboratory of Pathophysiology, Institute of Gerontology, Academy of Medical Sciences of the USSR, Kiev. (Presented by Academician of the Academy of Medical Sciences of the USSR N. N. Gorev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 150–151, February, 1977.     

Effect of hypoxia on nicotinamide coenzyme content in tissues of newborn rats

The concentration of nicotinamide coenzymes (NAD, NADH, NADP, and NADPH) was determined in tissues of the brain, heart, and liver of newborn rats exposed for 2.5 h to a hypoxic atmosphere containing 4% oxygen. A marked decrease in the NAD content, an increase in NADH, and a decrease in the NAD/NADH ratio by more than half were observed in the experimental animals and the changes were particularly marked in the brain and heart. Under the same conditions there was a decrease in the NADPH content, chiefly in the liver, and in the total reserves of NAD-phosphates in the tissues of the newborn rats studied. It is suggested that hypoxia has a substantial effect on the absolute and relative concentration of nicotinamide coenzymes in the tissues of newborn rats, resulting in changes in the level and direction of oxidoreductive processes under hypoxic conditions.Scientific-Research Institute of Pediatrics, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR M. Ya. Studenikin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 11, pp. 1326–1328, November, 1976.     

Mechanism of regression of mammary gland carcinoma in lactating rats

The effect of the conditions of lactation on the frequency of regression of a transplantable mammary gland carcinoma RMK-1 was studied in albino rats. In rats feeding 8±1 young the tumor underwent regression in 47% of cases. After ovariectomy and administration of cortisone and oxytocin, which have an indirect inhibitory action on the secretion of FSH by the pituitary, the frequency of regression of tumors in rats feeding the same number of young rose to 71–81%. In rats with prolonged lactation, feeding 8±1 young for 2–2.5 months, and in rats with intensive lactation feeding litters of 13±2 young, regression of the tumors did not increase. The results confirm the validity of the hypothesis that, besides high secretion of pituitary FSH, a decrease in the secretion of pituitary LH plays a role in the regression of mammary gland carcinoma in the course of lactation.Oncologic Scientific Center, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR L. M. Shabad.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 5, pp. 582–585, May, 1978.     

Dynamics of spinal cord changes produced by prenatal asphyxia

Changes in neurons and nerve fibers of the spinal cord at the level C4–C5 were studied in rats exposed to asphyxiain utero and killed at different times. In the first 10 days the changes in the nerve cells progressed gradually. By the age of 1–2 months the state of most neurons is back to normal, but in each hundred fields of vision pathologically changed neurons are found, mainly in zones of the collateral circulation. Changes also are observed in the nerve fibers.Laboratory for the Study of Brain Development, Scientific-Research Institute of Pediatrics, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR M. Ya. Studenikin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 3, pp. 361–364, March, 1977.     

State of the nutritive circulation in rats after prolonged hypokinesia

After prolonged hypokinesia for 80–100 days considerable disturbances of the nutritive circulation were observed in experiments on rats: reduction of the network of true capillaries, emptying of the terminal arteries and arterioles, direction of the terminal blood flow mainly along the developing network of arteriovenous anastomoses, by-passing the nutritive vessels. A tendency was noted for the buffer bases to be low in the venous blood and for respiratory alkalosis to be present in the arterial blood. The hemorheological stages were not significant.Laboratory of Pathophysiology of Extremal States, Institute of General Pathology and Pathological Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 403–405, April, 1977.     

Effect of ethimizole on energy metabolism in the rat brain

In a dose of 25 mg/kg, 20 min after intraperitoneal injection, ethimizole stimulates oxidative phosphorylation, increases the creatine phosphate content and reduces the concentration of inorganic phosphorus in the brain tissue of rats. It is postulated that ethimizole stimulates energy metabolism through its activating effect on adenyl cyclase.Laboratory of Experimental Pharmacology, Department of Pharmacology, Institute of Experimental Medicine, Academy of Medical Sciences of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR S. V. Anichkov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 2, pp. 185–187, February, 1977.     

Mechanism of action of aspirin on platelet function

Inhibition of platelet aggregation and of the reaction of liberation of platelet factor 3 under the influence of aspirin was shown to be due to the action of the drug not only on the platelets, but also on plasma cofactors: In experimentsin vitro the blood plasma of rats receiving aspirin reduced the aggregating power of the platelets of intact animals; blood plasma of intact rats increased the aggregating power and accessibility of factor 3 of the platelets of animals receiving aspirin.Department of Radiation Pathological Physiology, Scientific-Research Institute of Medical Radiology, Academy of Medical Sciences of the USSR, Obninsk. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Fedorov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 434–435, April, 1977.     

Changes in sialic acid content in the intestinal tissues of animals vaccinated with living poliomyelitis vaccine

A single oral administration of living poliomyelitis vaccine of immunologic type II (Sabin strain) to albino mice weighing 12–14 g is followed by an increase in the free sialic acid content from the 5th to the 20th days and in the bound sialic acid content from the 20th to the 45th day from the beginning of immunization in the small intestine of the vaccinated animals.Laboratory of Immunopathology, D. I. Ivanovskii Institute of Virology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. M. Zhdanov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 81, No. 3, pp. 298–299, March, 1976.     

Dynamics of transcallosal potentials during local action of a high temperature on the cerebral cortex

The effect of local heating of an area of the sensomotor cortex on transcallosal responses was studied in acute experiments on cats anesthetized with pentobarbital. Short and prolonged heating of localized areas of the cortex of both hemispheres, starting from temperatures above 44°C, was found to cause initial depression of the negative component of the transcallosal response, followed by irreversible blocking of both phases of the response within the range 47–49°C. It is concluded that the direct inhibitory effect of high temperatures on cortical neurons is manifested only within the range of extremal temperatures, incompatible with vital activity of the whole animal. Experiments with heat blocking of an area of the cortex of one hemisphere provide evidence that transcallosal responses may arise chiefly through direct stimulation of callosal fibers beneath the stimulating electrodes and may entirely reflect postsynaptic potentials.Central Research Laboratory, Rostov Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR P. N. Veselkin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 10, pp. 408–411, October, 1977.     

Character and frequency of pathological changes in the solitary rat kidney after removal of the other kidney in old age

One kidney was removed from male rats weighing 500–850 g; the remaining kidney underwent compensatory hypertrophy and, after 1–2 months, it was larger (index of hypertrophy 70–92%) in rats weighing 700–850 g than in animals weighing 500–600 g (56–58%). Histological investigation showed that this marked hypertrophy of the solitary kidney in old rats was not the result of disease of the organ, for pathological changes such as are sometimes found in intact and hypertrophied kidneys were found in only 38 of 223 animals. The results suggest that the ability of the kidneys to undergo, compensation and regeneration is not reduced in old age.Laboratory of Growth and Development, Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 9, pp. 362–366, September, 1977.     

Morphohistochemical study of the rat placenta after exposure to carbon tetrachloride at different stages of pregnancy

Intraventricular injection of CCl₄ (0.3 ml/100 g body weight) into female rats causes marked injury to the tissues of the placenta and, in particular, to the chorionic epithelium of the labyrinthine portion, with maximal development of degenerative and necrobiotic changes on the 14th–16th day of pregnancy (if the poison is injected 48 h before sacrifice). An increase in the number of mitotically dividing epithelial cells is observed at all times and the dimensions of the nuclei and nucleoli of the cytotrophoblastic cells are increased on the 17th–18th day of intrauterine development of the fetus. Injection of CCl₄ leads to a decrease in the content of histochemically detectable glycogen in the cytoplasm of the chorionic epithelium and a decrease in the content of amylase-resistant glycoproteins, protein, and RNA in the degenerating cells.Group for Fetoplacental Pathology, Institute of Clinical and Experimental Medicine, Siberian Branch, Academy of Medical Sciences of the USSR. Central Research Laboratory, Novosibirsk Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. D. Kaznacheev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 8, pp. 1007–1009, August, 1976.     

Comparison of compensatory hypertrophy of the kidney after unilateral nephrectomy on adult and senile rats

One kidney was removed from rats weighing 35–900 g. The animals were killed 2, 14, 30, and 60 days after the operation. The degree of compensatory hypertrophy of the remaining kidney varied considerably in the animals of different ages, although it was not reduced in old age. The weight of the hypertrophied kidney of the old rats 60 days after the operation was 55–92% of the combined weight of both kidneys in the control. Hypertrophy of the kidney at all ages was accompanied by increased proliferation of cells of the tubules, especially the proximal tubules. An increase in the size of the renal corpuscles during hypertrophy of the kidney was characteristic of rats of both age groups. However, with an increase in age this process developed faster and was more pronounced. At all times of investigation the hypertrophied kidney of rats of both ages contained 1. 5–2 times more open renal glomeruli than the kidney of the intact animal.Laboratory of Growth and Development, Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 11, pp. 1394–1397, November, 1976.     

Effect of chronic stimulation of rats with intact and deafferented hyplthalami on lipid metabolism and the adrenal cortex

Chronic stimulation of rats after a mock operation and rats with deafferented hypothalami leads to a decrease in the total cholesterol concentration in the blood and to the accumulation of triglycerides in the liver. Injection of dexamethasone into rats is accompanied by an increase in the blood cholesterol and triglyceride concentrations and accumulation of triglycerides in the liver. The action of dexamethasone is stronger in animals with a deafferented hypothalamus. The rate of secretion of 11-hydroxycorticosteroids into the adrenal vein was reduced in the latter.N. N. Anichkov Department of Atherosclerosis and Department of Pharmacology, Institute of Experimental Medicine, Academy of Medical Sciences of the USSR, Leningrad. (Presented by Academician of the Academy of Medical Sciences of the USSR A. N. Klimov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 3, pp. 289–291, March, 1977.     

Resistance of the myocardium to adrenalin in rats adapted to hypoxia

The intensity of the changes produced by adrenalin in the myocardium of rats adapted to hypoxia was studied after its administration to the intact animal and perfusion of the isolated heart. The changes were revealed by histochemical reactions for succinate dehydrogenase activity and staining for lipids. After intramuscular injection of a cardiotoxic dose of adrenalin (2.0 mg/kg) into adapted rats no damage to the myocardium was found, whereas perfusion of the isolated heart with adrenalin (20 g/ml) caused the formation of micronecroses of the cardiocytes. However, their volume was statistically significantly smaller than in the isolated heart of intact rats under similar conditions. Differences in the sensitivity of the myocardium in vivo and in vitro indicate that the phenomenon of protection of the myocardium against the harmful effects of adrenalin in rats adapted to hypoxia is manifested at the level of the intact organism. The increase in the resistance of the myocardium itself is probably due to an increase in the power of the metabolic systems during adaptation.Department of Pathological Physiology, Patrice Lumumba Peoples' Friendship University. Department of Geographic Pathology, Research Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 9, pp. 265–268, September, 1977.     

Effect of muscular exertion on invertase activity of the small intestine

Invertase activity of the proximal, middle, and distal parts of the small intestine after muscular exertion lasting 2, 4, and 10 h (forced swimming in water at 35±1°C) was studied in acute experiments on male albino rats. After swimming for 2 h the invertase activity in the first two parts of the intestine was sharply reduced and it returned to its initial level after 48–72 h. This decrease was much less marked in the distal portion. Swimming for both 4 and 10 h led to a slight increase in enzyme activity in all three parts of the intestine 24 h after the beginning of the experiments, followed by a decrease in the first two parts and a marked increase in the distal portion 48 h after the beginning of the experiment. It is suggested that these changes are brought about through the hypothalamic-pituitary-adrenal system in accordance with the principle of the general nonspecific adaptation syndrome.Laboratory of the Physiology of Digestion and Laboratory of General Physiology, Institute of Physiology, Academy of Sciences of the Uzbek SSR, Tashkent. (Presented by Academician of the Academy of Medical Sciences of the USSR N. A. Yudaev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 82, No. 11, pp. 1335–1337, November, 1976.     

Investigation of the effect of certain chlorinated hydrocarbons on the composition of the hepatocyte population of the rat liver

Hepatocytes in the liver of albino rats poisoned by inhalation of dichloropropane and trichloropropane were investigated cytophotometrically and karyometrically. With respect to the effect on polyploidization of the hepatocyte nuclei trichloropropane was found to be more toxic than dichloropropane. The development of polyploidization is determined by the dose of the toxic agent and the exposure to it: The smaller the dose the shorter the time required for the effect to take place.Laboratory of Morphology, A. N. Sysin Institute of General and Communal Hygiene, Academy of Medical Sciences of the USSR. Laboratory of Cytology, N. K. Kol'tsov Institute of Developmental Biology, Academy of Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 3, pp. 345–348, March, 1977.     

A rapid method of inducing amyloidosis in mice

A new modification of the casein model of amyloidosis in mice is suggested, whereby the time for development of amyloidosis is reduced to 5–10 days.Laboratory of General Pathological Anatomy, Institute of Human Morphology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 85, No. 5, pp. 634–635, May, 1978.