Whole brain methionine-enkephalin of ethanol-avoiding and ethanol-preferring C57BL mice

Summary These experiments systematically investigated ethanol preference in both the C57Bl/6N and C57Bl/6J mice utilizing three-choice 2-bottle preference test. In addition, these sublines were evaluated for whole brain methionineenkephalin levels, which were significantly lower in C57Bl/6J mice (alcohol preferring) compared to C57Bl/6N mice (alcohol non-preferring). This finding supports the involvement of the peptidyl opiates in ethanol seeking behavior.     

Saccharin preference of butyraldoxime-treated C57BL mice

Zusammenfassung Butyraldoxim, das in C57BL-Mäusen bevorzugtes Alkoholtrinken vermindert, wurde im 2-Wahl-Vorzugsversuch in Wasser oder Saccharinlösung verabreicht und führte zu keiner konditionierten Aversion. Das Ergebnis bestätigt die Hypothese, der Butyraldoxim-Effekt beruhe auf spezifisch metabolischer Wechselwirkung mit Alkohol.     

Pigment in the spleen of C57BL/10ScSn and related mice

Summary Pigment present in the spleen of C57BL and related mice, after the stress of experimental procedures, was shown to be melanin.Acknowledgments. We would like to thank Dr. J. Hewson, British Industrial Biological Research Association, Carshalton, Surrey, for the help and advice.     

Ultrastructure of muscle spindles in C57BL/6Jdy 2J/dy 2J dystrophic mice

Summary The sensory organs of skeletal muscles, the muscle spindles, were examined using electron microscopy indy ^2J/dy ^2J dystrophic mice. Despite widespread damage to the extrafusal (skeletomotor) fibres the intrafusal (spindle) fibres appeared normal and seemed resistant to the aetiological factors for murine dystrophy.This work was supported by grants from the Medical Research Council and the Science Research Council of Great Britain.     

Ultrastructure of muscle spindles in C57BL/6J dy2J/dy2J dystrophic mice.

The sensory organs of skeletal muscles, the muscle spindles, were examined using electron microscopy in dy2J/dy2J dystrophic mice. Despite widespread damage to the extrafusal (skeletomotor) fibres the intrafusal (spindle) fibres appeared normal and seemed resistant to the aetiological factors for murine dystrophy.     

Efficacy of ethanol as a discriminative stimulus in ethanol-preferring and ethanol-nonpreferring rats

Rats which exhibited a preference for drinking a 6% w/v solution of ethanol in a free choice situation did not differ in their sensitivity to ethanol from animals exhibiting an aversion for ethanol, as measured by leaning rates in a T-maze task in which ethanol served as a discriminative stimulus.     

Effect of the administration of (d-Ala)2methionine-enkephalin on the serotonin metabolism in rat brain

Summary The effect of cerebroventricular injection of [D-Alanine] methionine-enkephalin (DALA), a synthetic analog of met-enkephalin, on the serotonergic system of rat brain has been studied. This opioid peptide caused an increase in 5HT turnover which was particularly evident in the limbic forebrain. This effect was completely antagonized by naloxone pretreatment.Acknowledgments. Support received from Tecnofarmaci, Rome, is gratefully acknowledged.     

Efficacy of ethanol as a discriminative stimulus in ethanol-preferring and ethanol-nonpreferring rats

Summary Rats which exhibited a preference for drinking a 6% w/v solution of ethanol in a free choice situation did not differ in their sensitivity to ethanol from animals exhibiting an aversion for ethanol, as measured by learning rates in a T-maze task in which ethanol served as a discriminative stimulus.The author is thankful to Miss Christine Currey for technical assistance.     

Dystrophic mutation (dy2J) affecting regulation of lactate dehydrogenase (LDH) and pyruvate kinase (PK) in C57BL/6J mice

Summary The genotype difference (dystrophic vs nondystrophic) in the LDH isozymes is observed in kidney. These differences are evident only at birth and at early developmental stages (before the expression of dystrophic symptoms). The tissue specific genotype differences for PK are limited to the thigh muscle (M form) and heart (L form), after the onset of the condition. These differences may reflect the pleiotropic effect of the dy^2J locus during the temporal regulation of these and other enzymes implicated in muscular dystrophy (MD).This research was financed by a Natural Sciences and Engineering Research Council Canada grant to S.M.S.     

Expression of an antigen associated with Gross virus on the surfaces of murine cells producing an oncornavirus from the radioleukemia of C57BL/6 mice]

A leukemogenic viral complex was demonstrated in cultures of 13-3 C cell line derived from a C57BL/6, radiation leukemia virus (RadLV-Rs) induced tumor. Both 13-3C and leukemic cells induced in C57BL/6 mice by 13-3C virus carry a cell surface antigen associated with Gross leukemia virus (GCSAa). These findings point to a close similarity between these antigens and those of murine endogenous ecotropic viruses.     

Glutamate oxaloacetate transaminase (GOT) in thedy 2J genotypes of C57BL/6J mice: Possible involvement of regulatory defect in muscular dystrophy

Summary The GOT mitochondrial isozyme of heterozygote and homozygote muscular dystrophy (dy^2J) genotypes is affected during development prior to the expression of dystrophy in homozygotes, dy^2J/dy^2J.This research was supported by a Natural Science and Engineering Research Council Canada grant to S.M.S.     

Preferential excretion of glycated albumin in C57BL-Ks-J mice: Effects of diabetes

Urinary excretion of glycated albumin was quantitated in genetically hyperglycemic mice (C57BL-Ks-J, db/db mice), a model for non-insulin-dependent diabetes mellitus, and compared with their non-diabetic littermates. The data indicated a preferential excretion of glycated albumin in non-diabetic mice. This phenomenon of editing of glycated albumin is decreased significantly in diabetic mice. Quantitative measurements of overall excretion of glycated albumin suggested that the loss of editing in diabetic mice is due to the dilution of glycated albumin by the unmodified albumin which is excreted in large amounts in diabetic mice. Therefore, the loss of editing observed in this model resembled the one we characterized in insulin-dependent diabetic humans and a streptozotocin-diabetic rat model³.     

Galactose transfer and UDP-Galactose hydrolysis in urine from normal balb/c and Balb/c YC8 mice

Summary By chromatographic method we have shown the existence of a complex system for galactose transfer from UDP-galactose and for nucleotide hydrolysis in urines from Balb/c YC8 and normal Balb/c mice. By action of sera from normal and ascitic mice as source of enzyme, we have been able to detect transfer for galactose in urines from ascitic mice and an important inhibitory effect of the nucleotide sugar hydrolysis by the sera with urines from normal mice.     

Preferential excretion of glycated albumin in C57BL-Ks-J mice: effects of diabetes.

Urinary excretion of glycated albumin was quantitated in genetically hyperglycemic mice (C57BL-Ks-J, db/db mice), a model for non-insulin-dependent diabetes mellitus, and compared with their non-diabetic littermates. The data indicated a preferential excretion of glycated albumin in non-diabetic mice. This phenomenon of 'editing' of glycated albumin is decreased significantly in diabetic mice. Quantitative measurements of overall excretion of glycated albumin suggested that the loss of editing in diabetic mice is due to the dilution of glycated albumin by the unmodified albumin which is excreted in large amounts in diabetic mice. Therefore, the loss of editing observed in this model resembled the one we characterized in insulin-dependent diabetic humans and a streptozotocin-diabetic rat model.