SEASONAL ADJUSTMENTS IN CAPTURED WILD NORWAY RATS: I. ORGAN WEIGHTS, EAR VASCULARIZATION, AND HISTOLOGY OF EPIDERMIS

1961 ◽  
Vol 39 (12) ◽  
pp. 1865-1870 ◽  
Author(s):  
O. Héroux

Male wild rats (Rattus Norwegicus) captured during the winter had different organ weights from similar animals captured during the summer. These seasonal changes in organ weights were different from those observed in white rats acclimated to cold in a cold room (indoor) or acclimatized to winter outdoors in groups of 10 to a cage.Unlike both the indoor and outdoor cold-conditioned white rats, the wild rats, in winter, did not have a reduced muscle mass as compared to the summer-captured rats, or a reduced abdominal fat reserve, or an enlargement of the liver and kidney. The abdominal fat reserve actually increased during the winter.Like the outdoor white rats, the wild rats, during the winter, did not show the enlargement of the thyroids, adrenals, pituitary, and digestive tract or the reduction in pelt and the ear cold injury that were invariable outcomes of continuous individual exposure to a constant low-temperature indoors. Like the indoor and unlike the outdoor white rats, however, they showed an hypertrophy of the heart and an increased vascularization of the ear.Because the wild rats trapped during the winter showed very few of the morphological changes usually found in cold-exposed white rats, it is suggested that winter conditions encountered were not stressful to the wild rats.

1962 ◽  
Vol 40 (1) ◽  
pp. 537-545 ◽  
Author(s):  
O. Héroux ◽  
Donna Wright

During the winter, wild rats (Rattus norwegicus) develop metabolic adjustments similar to those found in the white rats acclimated to cold in the laboratory. The rate of shivering found in the winter-captured wild rats is lower than that found in the summer-captured rats, indicating the presence of non-shivering thermogenesis. The metabolic response to noradrenaline is enhanced suggesting that non-shivering metabolism in these wild rats, as in the case of white rats, is mediated by noradrenaline. Unlike white rats acclimated to a constant cold temperature in the laboratory, but like white rats acclimatized to cold by group exposure to outdoor winter conditions, wild rats develop a greater pelt insulation in winter.


1962 ◽  
Vol 40 (4) ◽  
pp. 537-545 ◽  
Author(s):  
O. Héroux ◽  
Donna Wright

During the winter, wild rats (Rattus norwegicus) develop metabolic adjustments similar to those found in the white rats acclimated to cold in the laboratory. The rate of shivering found in the winter-captured wild rats is lower than that found in the summer-captured rats, indicating the presence of non-shivering thermogenesis. The metabolic response to noradrenaline is enhanced suggesting that non-shivering metabolism in these wild rats, as in the case of white rats, is mediated by noradrenaline. Unlike white rats acclimated to a constant cold temperature in the laboratory, but like white rats acclimatized to cold by group exposure to outdoor winter conditions, wild rats develop a greater pelt insulation in winter.


2007 ◽  
Vol 89 (1) ◽  
pp. 47-59 ◽  
Author(s):  
CHRISTINA NEUSCHL ◽  
GUDRUN A. BROCKMANN ◽  
SARA A. KNOTT

Multiple-trait analyses have been shown to improve the detection of quantitative trait loci (QTLs) with multiple effects. Here we applied a multiple-trait approach on obesity- and growth-related traits that were surveyed in 275 F2 mice generated from an intercross between the high body weight selected line NMRI8 and DBA/2 as lean control. The parental lines differed 2·5-fold in body weight at the age of 6 weeks. Within the F2 population, the correlations between body weight and weights of abdominal fat weight, muscle, liver and kidney at the age of 6 weeks were about 0·8. A least squares multiple-trait QTL analysis was performed on these data to understand more precisely the cause of the genetic correlation between body weight, body composition traits and weights of inner organs. Regions on Chr 1, 2, 7 and 14 for body weights at different early ages and regions on Chr 1, 2, 4, 7, 14, 17 and 19 for organ weights at 6 weeks were found to have significant multiple effects at the genome-wide level.


Author(s):  
B.A. Katsnelson ◽  
M.P. Sutunkova ◽  
L.I. Privalova ◽  
S.N. Solovjeva ◽  
V.B. Gurvich ◽  
...  

The article presents in an experiment obtained principal results based on repeated low-level inhalation exposures of laboratory animals (white rats, outbred) to nickel oxide nanoparticles with a diameter of (23 ± 5) nm, 4 hours a day, 5 times a week for up to 10 months in a «nose only» installation. It was shown that non-specific body reactions to the action of NiO NPs include: diverse manifestations of systemic toxicity with a particularly pronounced influence on liver and kidney function, redox balance, damage to some areas of brain tissue, associated with proven movement of the nanoparticles themselves from the nasal mucosa along the olfactory tract; some cytological signs of probable development for allergic syndrome; paradoxically low severity of pulmonary pathology by pneumoconiotic type explained by a small chronic delay of nanoparticles in the lungs; the genotoxic effect of the organismal level, even at those low levels of chronic exposure, at which systemic toxicity is rather poorly. Along with that, NiO NPs also induce phase-stimulation of erythropoiesis, which is relatively specific for the toxic nickel effects.


Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 565
Author(s):  
Zehui Liu ◽  
Hulong Lei ◽  
Renyong Tang ◽  
Junhua Yang ◽  
Xiulan Guo ◽  
...  

Decabrominated diphenyl ether (BDE-209) is widely used as a flame retardant and is detected at high levels in the environment. Its toxicities have been reported and have attracted attention. In the present study, broilers were used to determine the response in growth performance, carcass traits, meat quality, blood profiles and antioxidant system to BDE-209 exposure at doses of 0, 0.02, 0.4 and 4 mg/kg. The results showed that BDE-209 exposure at levels of 0.02 or 0.4 mg/kg increased feed intake and decreased feed efficiency. BDE-209 altered the blood profiles, such as reducing the numbers of white blood cells, lymphocytes and neutrophilic granulocytes. As compared with the control, BDE-209 exposure significantly increased abdominal fat percentages of broilers at 64.9–159.5% and adversely affected the selected biochemical indicators, including alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine (CRE), which indicated its toxicity to liver and kidney functions. Moreover, BDE-209 exposure significantly increased plasma malondialdehyde (MDA) concentrations and decreased the activities of glutathione peroxidase (GSH-px) and superoxide dismutase (SOD), which implied aggravating oxidant stress and decline of antioxidant capacity in broilers. In conclusion, our data demonstrated that the environmental pollutant BDE-209 adversely influenced growth performance, increased the deposition of abdominal fat, impaired antioxidant capacity and the immune system and had potential toxicity to the liver and kidney of broilers.


2020 ◽  
pp. 66-71
Author(s):  
Татьяна Геннадьевна Боровая ◽  
Владимир Григорьевич Жуховицкий ◽  
Мария Николаевна Черкасова

Цель - выявление реактивных изменений гистологических элементов печени и почек у мышей в экспериментальных моделях сепсиса, вызванного штаммами 1840 и 1623 Pseudomonas aeruginosa (PsA1840, 1623). Материал и методы. Сепсис моделировали на двух группах половозрелых самцов мышей линии C57Bl/6 интраперитонеальным введением Pseudomonas aeruginosa. Животным 1-й группы (8 особей) вводили штамм 1840, животным 2-й группы (12 особей) - штамм 1623. Контрольная группа состояла из 3 животных. Перед началом опыта штаммы тестировали на присутствие генов экзотоксинов U, S, T, Y (ExoU, ExoS, ExoT, ExoY) с помощью полимеразной цепной реакции (ПЦР). Для визуализации продуктов ПЦР применяли электрофорез в горизонтальном 1,5 % агарозном геле. Животных вскрывали на терминальной стадии сепсиса. Серийные парафиновые срезы печени и почек толщиной 4 мкм окрашивали гематоксилином - эозином, анализировали особенности гистоструктуры органов и фотографировали в световом микроскопе «AxioPlus» (фирма Zeiss, Германия). Результаты. Штамм PsA 1840, имеющий ген exoU, вызывал выраженные деструктивные изменения пластинок гепатоцитов и замещение участков паренхимы печени гомогенным эозинофильным веществом. Присутствовали признаки стаза крови в синусоидных капиллярах, расширение и тромбоз центральных вен, немногочисленные скопления лейкоцитов. Морфологические изменения нефронов состояли в локальных деструктивных изменениях проксимальных канальцев на периферии коркового вещества почек. При введении PsA1623, имеющего ген exoS, возникали массовая гибель почечных телец и дегенерация канальцев нефронов. В печени дольковая гистоархитектура в основном сохранялась. Выводы. Предполагается связь выявленных различий в реактивных изменениях гистологических элементов печени и почек в подопытных группах с особенностями геномов штаммов PsA, использованных для моделирования сепсиса. Objective - to identify reactive changes of liver and kidney histological elements in experimental models of sepsis in mice caused by 1840 and 1623 Pseudomonas aeruginosa strains (PsA1840, 1623). Material and methods. Sepsis was modeled in two groups of mature male C57Bl/6 mice by intraperitoneal administration of Pseudomonas aeruginosa. Strain 1840 was administered to animals of the first group (n=8), animals of the second group (n=12) were administered strain 1623; the control group consisted of 3 animals. Before the experiment, the strains were tested for the presence of genes of exotoxins U, S, T, Y (ExoU, ExoS, ExoT, ExoY) using polymerase chain reaction (PCR). Electrophoresis in horizontal 1,5 % agarose gel was used to visualize PCR products. The animals were euthanized at the terminal stage of sepsis. The extracted liver and kidneys were fixed according to the generally accepted histological method, and embedded into paraffin blocks. Serial 4 μm thick sections of organs were stained with hematoxylin and eosin, analyzed and photographed using «AxioPlus» light microscope (Zeiss, Germany). Results. Strain PsA 1840, carrying the gene of exotoxin U (ExoU), caused severe destructive changes of hepatocytes plates and the replacement of the liver parenchyma with homogeneous eosinophilic substance. There were signs of blood stasis in sinusoidal capillaries, expansion and thrombosis of central veins, a few accumulations of leukocytes. Morphological changes of nephrons consisted of local destructive changes in the proximal tubules at the periphery of kidney cortical substance. After the introduction of PsA1623, carrying the gene of exotoxin S (ExoS), the massive death of renal corpuscles and degeneration of nephron tubules were registered. However, the lobular histoarchitecture in the liver remained mostly unaltered. Conclusions. It is supposed that there is a possible connection of the observed differences in reactive changes of liver and kidney histological elements in two experimental groups with genome features of PsA strains used for the sepsis modeling.


2019 ◽  
Vol 98 (10) ◽  
pp. 1161-1165
Author(s):  
Larisa M. Sosedova ◽  
E. A. Titov ◽  
M. A. Novikov ◽  
V. A. Vokina ◽  
V. S. Rukavishnikov

Introduction. In recent years, magnetic nanoparticles, which can simultaneously have a therapeutic effect on the pathological focus, are used to magnify contrast enhancement and increase diagnostic sensitivity during magnetic resonance therapy (MRT). The last is carried out by the effective capture of neutrons, which among all the chemical elements is most pronounced in gadolinium. The use of gadolinium nanoparticles encapsulated in a polymeric matrix allows increasing the bioavailability of nanoparticles, reduces the possible toxicity of drugs. Aim. Evaluation of impact of new nanocomposite magnetically active metal complex gadolinium system on the morphofunctional state of the nervous tissue, liver, and kidney of rats. Material and methods. Experimental studies of biological effects of gadolinium-arabinogalactan nanocomposite (Gd-AG) were carried out on rats that were injected intraperitoneally for 10 days at the dose of 500 μg/kg in 0.5 ml of saline. Animals were sacrificed by decapitation under light ether anesthesia the next day after the end of exposure. To perform pathological studies, frontal sections of the temporal-parietal zone of the sensorimotor cortex, liver and kidney tissues were stained on ordinary histological glass slides with hematoxylin and eosin for viewing microscopic picture. The immunohistochemical method was used to determine the activity of the bcl-2, caspase-3 and hsp70 modulatory protein in apoptosis of white rats in brain neurons and to study the biological response of the organism at the subcellular level. Results. Histological analysis of tissues revealed a pronounced compensatory response of liver, a violation of the functional activity of kidneys. A decrease in the total number of normal neurons per unit area in brain tissue and an increase in the number of acts of neuronophagy indicate the initial stage of neurodegenerative process. Evaluation of the intracellular metabolism of neurons has not established the presence of signs characteristic of apoptotic process. Conclusion. The subacute effect of Gd-AG in a dose of 500 µg/kg causes a disturbance of morphofunctional state of liver, kidneys and nervous tissue, as well as modulation of cellular proteomics.


1958 ◽  
Vol 36 (2) ◽  
pp. 209-216 ◽  
Author(s):  
O. Heroux ◽  
N. T. Gridgeman

In experiments in which two groups of animals of different mean body weight are compared, individual organ weights of the animals can be expressed as absolute weights, as fractional weights, or as absolute weights statistically regressed onto constant body weights. The second, and commonest, mode of expression involves the assumption that the part is directly proportional to the whole, and this is shown to be unlikely for all organs except the muscle mass. Practical as well as theoretical justifications for the use of regressed weights (which utilize the actual slope of the line relating the organ weight to the whole) are given.The experimental data are from white rats kept for 4 weeks in a warm (30 °C.) or a cold (6 °C.) environment. It is shown that cold adaptation had no effect on brain, genitals, and lung weights, but that it reduced the growth of muscle, pelt, fat, skeleton, spleen, and thymus, and that it hypertrophied the liver, intestine, kidney, heart, and adrenals. Apparently cold acclimated rats are smaller than the controls mainly because they have a smaller muscle mass.


1963 ◽  
Vol 41 (1) ◽  
pp. 1147-1153
Author(s):  
J. S. Willmer ◽  
O. Héroux

The in vitro adrenal steroid secretion of wild Norway rats (Rattus norvegicus) captured during the winter differed in quantity, but not in quality, from that of similar rats captured during the summer. Whereas there was no evident seasonal effect on adrenal weight either in males or in females, adrenals of both sexes secreted at a faster rate during the winter than during the summer, this increase involving the four groups of steroids characterized chromatographically during both seasons and in both sexes; the predominant steroid secreted was corticosterone. This seasonal adjustment in adrenal activity is similar to that observed in white rats kept in group cages exposed outdoors to the natural summer and winter environmental conditions, but it differs from that found in white rats cold-acclimated in the laboratory, in which adrenal activity is lower than normal after cold acclimation.


2015 ◽  
Vol 6 (4) ◽  
pp. 51-55 ◽  
Author(s):  
Petr Vladimirovich Pugach ◽  
Sergey Vladimirovich Kruglov ◽  
Natalia Rafailovna Karelina ◽  
Dmitriy Vitalievich Breusenko ◽  
Stepan Yurevich Bazhin ◽  
...  

The present study was undertaken to examine the structural features of the thymus and cranial mesenteric lymph nodes of newborn rats that have occurred as a result of antenatal alcohol intoxication. We used a set of morphometric, anatomical and histological methods. A study of the cranial mesenteric lymph nodes performed on 45 newborn rats born to 18 female mongrel white rats seven months of age. The studies were conducted in compliance with the order of the Ministry of Health of the USSR N 755 from 12.08.1977 and the order of the Ministry of Higher and Secondary Special Education of the USSR from 13.11.1984, "On the rules of work with experimental animals". Females, on which was received investigated offspring exposed to 15 % ethanol as the sole source of fluid for 1 week, one and three months before pregnancy, during pregnancy and after its completion. It is shown that depending on the duration of pregravid exposure to ethanol occur progredient changes in the structure of the thymus and cranial mesenteric lymph nodes. In the thymus, as well as in the lymph nodes, decreases the number of lymphoid cells and stromal elements content increases. In lymph nodes there are significant changes in the structure of the sinus system. The severity of the identified morphological changes due to the duration of the effects of alcohol on the system "mother-placenta-fetus”.


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