Exercise inhibits progressive growth of the Morris hepatoma 7777 in male and female rats

1989 ◽  
Vol 67 (8) ◽  
pp. 864-870 ◽  
Author(s):  
Vickie E. Baracos

Male and female rats were either trained to swim for a 6-week period or they remained sedentary. Rats were implanted with Morris hepatoma 7777 after 3 weeks of swimming and were sacrificed after a further 3 weeks. Exercised rats of both sexes showed a significant reduction in tumour weight at sacrifice, compared with sedentary controls (p < 0.01). Similarly, when rats were first implanted with tumours and then placed on an exercise program of 3 weeks duration, tumour growth was also reduced (p < 0.05). These results suggest that the tumour may be sensitive to exercise at more than one point in its development. Tumour growth was inhibited to a similar extent whether the total swimming time was 10, 20, or 30 h over the 3-week period. Although sedentary, tumour-bearing rats were anorexic; both male and female rats showed significant improvement of appetite during the period of tumour growth, in response to exercise. Tumour implantation was associated with significant losses of whole body and muscle protein. The progression of this wasting was not significantly altered by exercise.Key words: Morris hepatoma 7777, cancer, tumour, exercise, skeletal muscle, cachexia, protein.

2016 ◽  
Vol 33 (5) ◽  
pp. 385-405 ◽  
Author(s):  
Kristen R Ryan ◽  
Mark F Cesta ◽  
Ronald Herbert ◽  
Amy Brix ◽  
Michelle Cora ◽  
...  

Metalworking fluids (MWFs) are complex formulations designed for effective lubricating, cooling, and cleaning tools and parts during machining operations. Adverse health effects such as respiratory symptoms, dermatitis, and cancer have been reported in workers exposed to MWFs. Several constituents of MWFs have been implicated in toxicity and have been removed from the formulations over the years. However, animal studies with newer MWFs demonstrate that they continue to pose a health risk. This investigation examines the hypothesis that unrecognized health hazards exist in currently marketed MWF formulations that are presumed to be safe based on hazard assessments of individual ingredients. In vivo 13-week inhalation studies were designed to characterize and compare the potential toxicity of four MWFs: Trim VX, Cimstar 3800, Trim SC210, and Syntilo 1023. Male and female Wistar Han rats or Fischer 344N/Tac rats and B6C3F1/N mice were exposed to MWFs via whole-body inhalation at concentrations of 0, 25, 50, 100, 200, or 400 mg/m3 for 13 weeks, after which, survival, body and organ weights, hematology and clinical chemistry, histopathology, and genotoxicity were assessed following exposure. Although high concentrations were used, survival was not affected and toxicity was primarily within the respiratory tract of male and female rats and mice. Minor variances in toxicity were attributed to differences among species as well as in the chemical components of each MWF. Pulmonary fibrosis was present only in rats and mice exposed to Trim VX. These data confirm that newer MWFs have the potential to cause respiratory toxicity in workers who are repeatedly exposed via inhalation.


2000 ◽  
Vol 19 (2) ◽  
pp. 69-83 ◽  
Author(s):  
William J. Brock ◽  
David P. Kelly ◽  
Susan M. Munley ◽  
Karin S. Bentley ◽  
Kathy M. McGown ◽  
...  

The acute, subchronic, and developmental and genetic toxicity of hydrofluorocarbon (HFC)-236fa and HFC-236ea were evaluated to assist in establishing proper handling guidance. In acute inhalation studies, rats were exposed whole body for 4 hours to various concentrations of each isomer. Based on the lack of mortality, the approximate lethal concentration for HFC-236ea for male rats was > 85,000 ppm. For HFC-236fa, the LC50 for males and females (combined) was > 457,000 ppm. Narcotic-like effects, e.g., prostration, incoordination, and reduced motor activity, were observed only during exposure to either isomer, but were not evident after termination of exposure. In cardiac sensitization studies, HFC-236ea induced cardiac sensitization at ≥ 35,000 ppm, with fatal responses occurring at 50,000 ppm and greater. For HFC-236fa, a cardiac sensitization response was observed at 150,000 ppm and greater but not at 100,000 ppm. A fatal cardiac sensitization response was observed in one dog exposed to 150,000 ppm HFC-236fa. In 90-day subchronic inhalation studies, male and female rats were exposed whole body to HFC-236ea at concentrations of 0, 5000, 20,000, or 50,000 ppm for 6 hours/day, 5 days/week. Similarly, male and female rats were exposed whole body to HFC-236fa at concentrations of 0, 5000, 20,000, or 50,000 ppm for 6 hours/day, 5 days/week. During exposure, narcotic-like effect (reduced acoustic startle response) was observed at 50,000 ppm with both isomers, although there appeared to be an adaptive response to this effect as the study progressed. With HFC-236ea, dilatation of the seminiferous tubules, without effects on germ or Sertoli cells, was observed only in rats at 50,000 ppm. No other effects on in-life measures or on clinical or anatomic pathology, including histopathology, were observed for either isomer. In rat developmental toxicity studies, no evidence of embryotoxicity or teratogenicity was observed with either isomer exposed up to 50,000 ppm during gestational days 7 to 16. Also, no developmental toxicity was observed in rabbits exposed to HFC-236fa at concentrations of up to 50,000 ppm during gestational days 7 to 19. Neither of the HFC-236 isomers was mutagenic in the Ames reverse mutation assay or clastogenic in the chromosomal aberration assay with human lymphocytes. No increase in chromosomal aberrations was observed in in vivo micronucleus studies with either isomer.


2021 ◽  
Author(s):  
Fariborz Nowzari ◽  
Farhad Rahmanifar ◽  
Nader Tanideh ◽  
Mohammad Reza Dorvash ◽  
Arezoo Khoradmehr ◽  
...  

Abstract Effects of cottonseed flour in male and female rats’ fertility based on hormonal and histomorphometry changes were studied. Sixty-four Sprague-Dawley adult male and female rats were randomly divided into control and treatment groups. Treatment group was received diets containing cottonseed flour for 35 days. Control group was given standard rat food. Body and testis weights, epididymis semen evaluation indices and serum sex steroid hormones were determined. Histomorphometry alterations of testes and ovary were evaluated. Then, normal female and male rats were mated by rats in both groups and after 35 days, number of pups was measured. However, there was no significant difference in whole body and testes weights, sperm concentration and viability between the control and treatment groups, respectively. Moreover, sperm motility in the treatment rats was significantly lower than the control group. Serum hormones alterations were not significant, but histomorphometry evaluations of testes showed significant changes in the testis structures after chronic consumption of cottonseed flour. In the female rats, body weight did not have significant difference between the treatment and control groups. Histomorphometry data in female ovary showed significant reduction of primary follicle volume and number in the treatment group against control. Follicle stimulating hormone showed insignificant reduction in the treatment group. Number of pups was significantly reduced in the female rats fed by cottonseed flour. Cottonseed flour in rat diet had adverse effects on rat reproduction. Therefore, it can be used as an efficient product for control of the rat population as a natural rodenticide agent.


2008 ◽  
Vol 27 (6) ◽  
pp. 427-439 ◽  
Author(s):  
Ronald S. Slesinski ◽  
Duncan Turnbull

Male and female Han Wistar rats were exposed for 6 h/day, 5 days/week for 13 or 104 weeks (whole body) to a magnetite photocopying toner. The toner contained 45% to 50% magnetite, with 45% to 50% styrene acrylic resin and less than 5% external additives, including hydrophobic amorphous silica and proprietary surface functional modifiers. Exposure levels were 1, 5, and 25 mg/m3 for the 13-week study and 1, 4, and 16 mg/m3 for the 104-week study. Lung toner burdens averaged 36, 288, and 604 μg per lung after 104 weeks’ exposure at 1, 4, and 16 mg/m3. The lung burdens were lower than have been reported in a similar study with a carbon-based toner. There were no significant effects on weight gain or food consumption in either study, or on clinical pathology parameters examined in the 13-week study. After 104 weeks’ exposure at 16 mg/m3, macroscopic examination revealed dark discoloration of the lungs and associated lymph nodes. Lung weights were significantly elevated by 21% and 14% for male and female rats, respectively. Microscopic findings indicative of a mild inflammatory response were similar in both studies, and included the presence of black-pigmented macrophages in the lungs and tracheobronchial and mediastinal lymph nodes; increased incidences of perivascular/peribronchiolar inflammatory cell infiltration; inflammation of the alveolar ducts (characterized by aggregations of black-pigmented alveolar macrophages and interstitial lymphocytic infiltration); increased cellularity of the bronchiole-associated lymphoid tissue; and a few instances of alveolar ciliated metaplasia. The 104-week study showed no increase in the incidence of pulmonary tumors.


1982 ◽  
Vol 27 (2) ◽  
pp. 254-259 ◽  
Author(s):  
Edward B. Tapscott ◽  
George J. Kasperek ◽  
G.Lynis Dohm

2015 ◽  
Vol 34 (6) ◽  
pp. 491-499 ◽  
Author(s):  
Ilseob Shim ◽  
Hyun-mi Kim ◽  
Sangyoung Yang ◽  
Min Choi ◽  
Gyun-baek Seo ◽  
...  

Talc is a mineral that is widely used in cosmetic products, antiseptics, paints, and rubber manufacturing. Although the toxicological effects of talc have been studied extensively, until now no detailed inhalation study of talc focusing on oxidative stress has been done. This repeated 4 weeks whole-body inhalation toxicity study of talc involved Sprague-Dawley rats. Male and female groups of rats were exposed to inhaled talc at 0, 5, 50, and 100 mg/m3 for 6 hours daily, 5 days/week for 4 weeks. The objective was to identify the 4-week inhalation toxicity of talc and investigate antioxidant activity after exposure to talc. There were no treatment-related symptoms or mortality in rats treated with talc. Glucose (GLU) was decreased significantly in male rats exposed to 50 and 100 mg/m3 of talc. Histopathological examination revealed infiltration of macrophages on the alveolar walls and spaces near the terminal and respiratory bronchioles. In male and female rats exposed to 100 mg/m3 talc, expression of superoxide dismutase 2, a typical biological indicator of oxidative damage, was significantly increased. Thus, inhalation of talc induces macrophage aggregations and oxidative damage in the lung.


1971 ◽  
Vol 123 (2) ◽  
pp. 261-266 ◽  
Author(s):  
J. O. Dolly ◽  
C. G. Curtis ◽  
K. S. Dodgson ◽  
F. A. Rose

Intraperitoneal, intravenous or oral administration of sodium oestrone [35S]-sulphate to male and female Medical Research Council hooded rats is followed by the rapid excretion of the bulk of the radioactivity in urine in the form of inorganic [35S]sulphate. Pre-treatment of rats with an antibiotic regimen does not affect the results except in the case of oral administration, when relatively large amounts of the dose are recovered as ester [35S]sulphate in faeces. Intravenous administration of the labelled ester to male and female rats with cannulae in bile duct and ureter gave results similar to those obtained with free-range animals. Only small amounts of radioactivity appeared in bile and this was mainly in the form of ester sulphate, including both oestrone [35S]sulphate and oestradiol-17β 3[35S]-sulphate. Whole-body radioautography pinpointed the liver as the probable site of the desulphation of the sulphate ester and this was confirmed by liver and kidney perfusion experiments and by studies with rats in which kidney function had been eliminated by ligation of the renal pedicles.


1961 ◽  
Vol 38 (1) ◽  
pp. 50-58 ◽  
Author(s):  
N. E. Borglin ◽  
L. Bjersing

ABSTRACT Oestriol (oestra-1,3,5(10)-triene-3,16α,17β-triol) is a weakly oestrogenic substance which, however, in contrast to what was formerly believed, is of physiological significance. Its effect is localized largely to the uterine cervix and vagina. Clinical experience argues both for and against an effect on the pituitary gland. This investigation is concerned with the morphological changes in the pituitary gland and adrenal cortex of gonadectomized male and female rats after the injection of oestriol. It was found that oestriol has the same type of action on these glands as other oestrogens, but under the experimental conditions used, this effect proved much weaker than that produced by oestradiol (oestra-1,3,5(10)-triene-3,17β-diol).


1973 ◽  
Vol 74 (1) ◽  
pp. 88-104 ◽  
Author(s):  
T. Jolín ◽  
M. J. Tarin ◽  
M. D. Garcia

ABSTRACT Male and female rats of varying ages were placad on a low iodine diet (LID) plus KClO4 or 6-propyl-2-thiouracil (PTU) or on the same diet supplemented with I (control rats). Goitrogenesis was also induced with LID plus PTU in gonadectomized animals of both sexes. The weight of the control and goitrogen treated animals, and the weight and iodine content of their thyroids were determined, as well as the plasma PBI, TSH, insulin and glucose levels. The pituitary GH-like protein content was assessed by disc electrophoresis on polyacrylamide gels. If goitrogenesis was induced in young rats of both sexes starting with rats of the same age, body weight (B.W.) and pituitary growth hormone (GH) content, it was found that both the males and females developed goitres of the same size. On the contrary, when goitrogenesis was induced in adult animals, it was found that male rats, that had larger B.W. and pituitary GH content than age-paired females, developed larger goitres. However, both male and female rats were in a hypothyroid condition of comparable degree as judged by the thyroidal iodine content and the plasma PBI and TSH levels. When all the data on the PTU or KClO4-treated male and female rats of varying age and B.W. were considered together, it was observed that the weights of the thyroids increased proportionally to B.W. However, a difference in the slope of the regression of the thyroid weight over B.W. was found between male and female rats, due to the fact that adult male rats develop larger goitres than female animals. In addition, in the male rats treated with PTU, gonadectomy decreased the B.W., pituitary content of GH-like protein and, concomitantly, the size of the goitre decreased; an opposite effect was induced by ovariectomy on the female animals. However, when goitrogenesis was induced in weight-paired adult rats of both sexes, the male animals still developed larger goitres than the females. Among all the parameters studied here, the only ones which appeared to bear a consistent relationship with the size of the goitres in rats of different sexes, treated with a given goitrogen, were the rate of body growth and the amount of a pituitary GH-like protein found before the onset of the goitrogen treatment. Moreover, though the pituitary content of the GH-like protein decreased as a consequence of goitrogen treatment, it was still somewhat higher in male that in female animals. The present results suggest that GH may somehow be involved in the mechanism by which male and female rats on goitrogens develop goitres of different sizes, despite equally high plasma TSH levels.


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