Pre- and postnatal distribution of lipids in the liver of genetic diabetic mice.

Triglycerides, phospholipids, cholesterol and cholesterol esters were determined by thin layer chromatography in the fetal and neonate livers of normal (Swiss albino) and genetic diabetic (KK) mice. In general, the lipids were elevated in the fetal liver of the KK mice. Despite this elevation in liver lipids, no increase in the weight of the newborn was observed.     

Growth metabolism of diaphragm in Swiss albino mice

Summary During the postnatal growth of diaphragm in swiss albino mice, a continuous decline in glycogen content reciprocates with the increasing SDH-activity and protein accumulation. An inverse relationship between DNA-contents and the basic protein levels points towards the regulatory behaviour of the latter during protein synthesis. While the variations in the contents of DNA and RNA speak of a feedback mechanism operative between the 2 nucleic acids during the postnatal growth, the fluctuations in RNA appear to be significant in determining the amount of acidic proteins, in this muscle.     

Growth metabolism of diaphragm in Swiss albino mice

During the postnatal growth of diaphragm in swiss albino mice, a continuous decline in glycogen content reciprocates with the increasing SDH-activity and protein accumulation. An inverse relationship between DNA-contents and the basic protein levels points towards the regulatory behaviour of the latter during protein synthesis. While the variations in the contents of DNA and RNA speak of a feedback mechanism operative between the 2 nucleic acids during the postnatal growth, the fluctuations in RNA appear to be significant in determining the amount of acidic proteins, in this muscle.     

Radiation protection of pronormoblasts and normoblasts by 2-mercaptopropionylglycine (MPG)

Summary The pronormoblasts and normoblasts in Swiss albino mice were found to be very sensitive to radiation and their percentage was reduced drastically after exposure to gamma-rays. The degree of damage increased with increase in radiation dose. MPG reduced the initial damage and brought about an early and fast recovery. It is concluded that the drug protects the stem cells and thereby reduces the depletion of the regenerating pool which causes a more efficient and accelerated recovery.     

Effect of low dose of 70 kVp X-rays on the intrauterine development of mice

Pregnant Swiss albino mice were exposed to low doses of X-rays (approximately 9 mGy) in the range used for diagnostic exposure, on day 3.5 of gestation (preimplantation period), day 6.5 (early organogenesis period) or day 11.5 (late organogenesis period). The fetuses were examined on the 18th day of gestation. Exposure at 3.5 days post coitus (d.p.c.) resulted in a significant increase in prenatal mortality, and an increased incidence of retarded fetuses was observed after exposure at 3.5 and 6.5 d.p.c. The major effect of exposure at 11.5 d.p.c. was a significant decrease in the fetal head size and brain weight.     

Arginase expression in peritoneal macrophages and increase in circulating polyamine levels in mice infected with Schistosoma mansoni

We investigated the nitric oxide (NO) synthase and arginase pathways in resident peritoneal macrophages of mice infected with the tropical parasite Schistosoma mansoni. The two enzymes may have opposite effects, insofar as NO may be involved in the killing of the parasite whereas arginase may stimulate parasite growth via polyamine synthesis. We determined the effects of the infection on the expression and activity of the two enzymes in macrophages, before and after cytokine activation. Cells from infected mice expressed the hepatic type I arginase, whereas in control cells, the enzyme was expressed only after cytokine activation, as were NO synthase II and type II arginase in both groups of cells. Moreover, we found that in infected mice, arginase expression in macrophages was associated with a ten fold increase in the concentration of circulating ornithine-derived polyamines. This may be of pathological importance, since parasitic helminths are though to be dependent on their hosts for the uptake and interconversion of polyamines. Received 13 March 2001; received after revision 4 May 2001; accepted 7 June 2001     

Effect of low dose of 70 kVp X-rays on the intrauterine development of mice

Summary Pregnant Swiss albino mice were exposed to low doses of X-rays (9 mGy) in the range used for diagnostic exposure, on day 3.5 of gestation (preimplantation period), day 6.5 (early organogenesis period) or day 11.5 (late organogenesis period). The fetuses were examined on the 18th day of gestation. Exposure at 3.5 days post coitus (d.p.c.) resulted in a significant increase in prenatal mortality, and an increased incidence of retarded fetuses was observed after exposure at 3.5 and 6.5 d.p.c. The major effect of exposure at 11.5 d.p.c. was a significant decrease in the fetal head size and brain weight.     

Role of grafted Schwann cells in the regeneration of intraspinal nerve fibers when peripheral nerve, skeletal muscle or submandibular gland fragments are transplanted into the spinal cord of the mouse

Small pieces of peripheral nerve, skeletal muscle or submandibular gland, taken from young or new-born mice, were grafted into the non-transected spinal cord of young albino mice, at the thoracic level, through a punctiform meningeal opening. Neighbouring intraspinal nerve fibres, severed during the grafting process, regenerate into and eventually throughout the transplants. In this regenerative process, sedentary or migrating Schwann cells of the transplants probably have a prominent influence in guiding the growth of the axonal sprouts they ensheathe and eventually myelinate.     

Dominant lethal mutations induced by14C in mice

Summary The mutagenic potential of 1.0 Ci¹⁴C was evaluated in Swiss albino male mice by the dominant lethal assay. A significant increase in post-implantation loss was seen, the maximum being in the 3rd week after treatment.Authors express their thanks to University Grants Commission, New Delhi, for financial assistance.     

Hymenolepis nana: Transfer of acquired immunity in mice through sensitized peritoneal exudate cells

Summary Sensitized peritoneal exudate cells from syngeneic donor Swiss albino mice infected with single and repeated doses of viable eggs ofHymenolepis nana produced a significant adoptive immunity in test mice when compared with animals which received non-sensitized (normal) cells. No significant difference was observed among the 2 recipient groups which received singly or repeatedly sensitized peritoneal exudate cells.Acknowledgment. We thank Professor B. M. Sinha for providing facilities and to the University Grants Commission, New Delhi for financial assistance.     

A simple method for sealing surgical skin wounds in young or new-born mice

Summary To close skin incisions in albino mice, a solution of polymethyl methacrylate in chloroform is recommended to be smeared over the wound, a procedure which virtually eliminates the incidence of maternal cannibalism.     

Circadian variation of diazepam acute toxicity in mice

Summary The LD₅₀ of i.p. injected diazepam was determined every 4 h over a 24-h period in albino mice adapted to a 12-h dark/12-h light programmed illumination cycle. Results show that diazepam is more toxic during the light phase of the cycle than during the dark phase and demonstrate circadian variation in the toxicity of the compound in mice.     

Enhancement of peritoneal macrophage activity by bovine gamma globulin in mice

Mice treated with bovine gamma globulins showed an increased resistance to Salmonella typhimurium infection. This phenomenon seems to be bound to an increase of peritoneal macrophage phagocytic activity, as shown by the method of chemiluminescence, in experiments performed on peritoneal macrophages from mice treated with bovine gamma globulin.     

Response of murine spermatocytes to the metaphase-arresting effect of several mitotic arrestants

Three mitotic arrestants, colchicine, Colcemid and vinblastine, were evaluated for their effects on producing meiotic arrest in the laboratory mouse. Colchicine is the most effective and its effect is both dose- and time-dependent. Treatment of mice with 40 mg/kg of colchicine for 3 h resulted in drastic improvement of the yield and quality of M-II figures. This treatment did not appear to increase the aneuploidy frequency in M-II's.     

The behavior of the homozygous and heterozygous sub-types of rats which are genetically-selected for diabetes insipidus: A comparison with Long Evans and Wistar stocks

Several aspects of spontaneous and conditioned behavior (food and water intake, locomotion and emotionality, passive and active avoidance acquisition and retention) of standard (albino and pigmented) rats, and rats heterozygous (HEDI) and homozygous (HODI) for diabetes insipidus, are reviewed. As would be expected, HODI rats have been repeatedly found to consume far more fluid than either HEDI or control rats. Pigmented rats appear to be more active than albinos. HODI rats exhibit less marked emotional responses than do control rats, among which the pigmented ones exhibit the highest emotionality. Light aversion is more evident in albino than in pigmented rats. No differences are found among HEDI, HODI and normal Long Evans rats. It is quite difficult to provide a clear-cut statement concerning inter-strain differences in passive avoidance behavior, possibly because of the variety of techniques employed. In any case, HODI rats do not perform worse than normal controls do. In one-way active avoidance paradigms, pigmented rats perform better than albinos, and the performance of HODI rats does not differ from that of controls. In two-way avoidance paradigms, albinos appear to outperform pigmented rats. Once again, there are no obvious differences between HODI and control animals.In addition to indicating that HODI rats may actually be less emotional than the other groups of rats reviewed here, the studies described once again fail to confirm the previously alleged functions of vasopressin in memory consolidation.     

The behavior of the homozygous and heterozygous sub-types of rats which are genetically-selected for diabetes insipidus: a comparison with Long Evans and Wistar stocks

Several aspects of spontaneous and conditioned behavior (food and water intake, locomotion and emotionality, passive and active avoidance acquisition and retention) of standard (albino and pigmented) rats, and rats heterozygous (HEDI) and homozygous (HODI) for diabetes insipidus, are reviewed. As would be expected, HODI rats have been repeatedly found to consume far more fluid than either HEDI or control rats. Pigmented rats appear to be more active than albinos. HODI rats exhibit less marked emotional responses than do control rats, among which the pigmented ones exhibit the highest emotionality. Light aversion is more evident in albino than in pigmented rats. No differences are found among HEDI, HODI and normal Long Evans rats. It is quite difficult to provide a clear-cut statement concerning inter-strain differences in passive avoidance behavior, possibly because of the variety of techniques employed. In any case, HODI rats do not perform worse than normal controls do. In one-way active avoidance paradigms, pigmented rats perform better than albinos, and the performance of HODI rats does not differ from that of controls. In two-way avoidance paradigms, albinos appear to outperform pigmented rats. Once again, there are no obvious differences between HODI and control animals. In addition to indicating that HODI rats may actually be less emotional than the other groups of rats reviewed here, the studies described once again fail to confirm the previously alleged functions of vasopressin in memory consolidation.     

Alteration of mitochondrial bioenergetics due to intravenous injection of a perfluorocarbon emulsion

Wistar albino rats were intravenously injected with 1 ml of an oxyphoretic emulsion of perfluorobutylfurane and killed 3, 7 or 30 days later. Mitochondria isolated from the liver and kidneys of treated rats showed a small decrease in the transmembrane electrical potential and a substantial depression of the rates of both ATP synthesis and ADP-stimulated respiration. These alterations in mitochondrial oxidative phosphorylation appear to be induced by perfluorocarbon and/or tensioactive molecules interacting with hydrophobic cell structures.     

Hepatic acid hydrolases of albino rats, Mastomys natalensis and albino mice during Plasmodium berghei infection

Changes in liver acid hydrolase activities during the infection of albino rats, Mastomys or mice with Plasmodium berghei are described. B-Glucosidase, B-galactosidase and N-acetyl-B-D-glucosaminidase exhibited widely different responses with acid phosphatase and cathepsin-B the least responsive and are likely to be causally related to immunity of animals.     

1,2-di-n-butylhydrazine dihydrochloride carcinogenesis in mice

Summary A solution of 0.0625% 1,2-di-n-butylhydrazine dihydrochloride (1,2-DBH) was given continuously in the drinking water of 6-week-old randomly bred albino Swiss mice for the remainder of their lives. The treatment gave rise to tumors of the lungs, lymphoreticular tissue and kidneys.     

Behavior and endocrine effects of 3,4,5-trimethoxyamphetamine in male mice

Summary Effects of single doses of 50 and 100 mg/kg of TMA given i.p. were noted in male albino mice after 40 min and 2 1/2 h. Locomotor activity was significantly altered and biochemical tests indicated stimulatory effects on adrenocortical and adrenomedullary functions due to TMA.