The effect of ethanol and cold-adaptation on the survival of guinea pigs in severe cold

1980 ◽  
Vol 85 (4) ◽  
Author(s):  
Pirkko Huttunen ◽  
J. Penttinen ◽  
J. Hirvonen
Keyword(s):  
Guinea Pigs ◽  
Cold Adaptation

Increased response to noradrenaline of isolated brown adipocytes from guinea pigs during cold-adaptation

1986 ◽  
Vol 14 (2) ◽  
pp. 282-283 ◽  
Author(s):  
JOHANNES RAFAEL ◽  
WALTRAUD FESSER ◽  
DAVID G. NICHOLLS
Keyword(s):  
Guinea Pigs ◽  
Cold Adaptation ◽  
Brown Adipocytes

scholarly journals Induction of functional uncoupling protein in guinea pigs infused with noradrenaline. Studies with isolated brown adipocytes

1987 ◽  
Vol 245 (2) ◽  
pp. 485-491 ◽  
Author(s):  
S A Cunningham ◽  
D G Nicholls
Keyword(s):  
Fatty Acid ◽  
Continuous Infusion ◽  
Guinea Pigs ◽  
Cold Adaptation ◽  
Uncoupling Protein ◽  
Mitochondrial Protein ◽  
Brown Adipocytes ◽  
Beta Agonists ◽  
Chronic Infusion ◽  
Isolated Adipocytes

Continuous infusion of noradrenaline over the interscapular brown fat of guinea pigs maintained at thermoneutrality (28-32 degrees C) induces changes similar to those after cold-adaptation. (1) Multilocular fat droplets appear within the brown adipocytes. (2) The number of mitochondria per adipocyte and the total number of adipocytes both increase. (3) Noradrenaline addition to isolated adipocytes causes near maximal uncontrolled respiration. (4) The cells become more sensitive to fatty acid-induced uncoupling. (5) The tissue-specific uncoupling protein per mg of mitochondrial protein is increased 5-fold. Specific alpha- and beta-agonists were also chronically infused. (6) Separate infusion of phenylephrine or isoprenaline was not able to stimulate mitochondriogenesis or hyperplasia. (7) Adipocytes from these animals could not be uncoupled by acute noradrenaline. (8) Simultaneous chronic infusion of phenylephrine and isoprenaline reproduced the effects of chronic noradrenaline infusion.

Changes induced by cold adaptation in the brown adipose tissue from several species of rodents, with special reference to the mitochondrial components

1979 ◽  
Vol 57 (11) ◽  
pp. 1262-1266 ◽  
Author(s):  
D. Ricquier ◽  
G. Mory ◽  
P. Hemon
Keyword(s):  
Molecular Weight ◽  
Adipose Tissue ◽  
Brown Adipose Tissue ◽  
Guinea Pigs ◽  
Cold Adaptation ◽  
Phospholipid Fatty Acid ◽  
Phospholipid Fatty Acid Composition ◽  
Brown Adipose ◽  
Total Tissue ◽  
Brown Fat Mitochondria

(1) The effects of cold adaptation upon the brown adipose tissue have been studied in rats, hamsters, mice, and guinea pigs.(2) Striking effects were found for total tissue as well as at the mitochondrial level, e.g., increases in protein and phospholipid contents, changes in phospholipid fatty acid composition (a decrease in the percentage of palmitic and palmitoleic acids and an increase in stearic and linoleic acids), and a change in the mitochondrial polypeptide composition (a marked increase in a 32 000 molecular weight polypeptide, except for hamsters).(3) In situations where animals exhibit a greatly enhanced capacity for nonshivering thermo-genesis (cold adaptation for rats, mice, and guinea pigs, birth for guinea pigs, and hibernation ability for hamsters, dormice, and garden dormice), brown fat mitochondria are characterized by the occurrence of large amounts of the 32 000 molecular weight polypeptide characteristic of these mitochondria.

Cold adaptation in guinea pig at level of isolated brown adipocyte

1986 ◽  
Vol 250 (2) ◽  
pp. C228-C235 ◽  
Author(s):  
J. Rafael ◽  
W. Fesser ◽  
D. G. Nicholls
Keyword(s):  
Guinea Pig ◽  
Cold Acclimation ◽  
Guinea Pigs ◽  
Cold Adaptation ◽  
Uncoupling Protein ◽  
Mitochondrial Protein ◽  
Respiratory Control ◽  
Cell Number ◽  
Brown Adipocyte ◽  
Brown Adipose

Isolated brown adipocytes were prepared from guinea pigs acclimated to 28 degrees C or exposed to 4-8 degrees C for periods of up to 3 wk. Cells from warm-adapted animals retained respiratory control when stimulated with norepinephrine. Cells from guinea pigs exposed to cold for 4-21 days showed a much greater respiratory response to norepinephrine due to enhanced uncoupling rather than enhanced substrate supply. After 7 days of cold acclimation, norepinephrine-stimulated respiration became uncontrolled and was limited only by the maximal respiratory capacity of the mitochondria. Three weeks of cold acclimation were accompanied by a doubling of total cell number, a doubling of the mitochondrial protein per adipocyte, and a sixfold increase in the norepinephrine-stimulated respiration per in situ mitochondrion with no change in respiratory chain capacity. The induction of norepinephrine-stimulated respiration correlated with the appearance of high-affinity purine nucleotide binding sites on the mitochondria, diagnostic of the uncoupling protein. If the results are extrapolated to the whole animal, they indicate that brown adipose tissue makes little contribution to thermogenesis in the warm-adapted guinea pig but may account for most or all the increment seen on cold adaptation.

Investigation of the relaxant effects of propofol on ovalbumin-induced asthma in guinea pigs

2006 ◽  
pp. 1
Author(s):  
I. Bagcivan ◽  
O. Cevit ◽  
M. K. Yildirim ◽  
S. Gursoy ◽  
S. Yildirim ◽  
...  
Keyword(s):  
Guinea Pigs

Hepatocyte Alterations in Guinea Pigs FED Polychlorinated Biphenyls (PCBs), Dibenzodioxins (PCDD), AND DIBENZOFURANS (PCDF)

1982 ◽  
Vol 40 ◽  
pp. 56-57
Author(s):  
J. N. Turner ◽  
D. N. Collins
Keyword(s):  
Guinea Pigs ◽  
Room Temperature ◽  
Dose Group ◽  
Methyl Cellulose ◽  
Uranyl Acetate ◽  
Target Organ ◽  
Office Building ◽  
Lead Citrate ◽  
Control Groups ◽  
Cooling Fluid

A fire involving an electric service transformer and its cooling fluid, a mixture of PCBs and chlorinated benzenes, contaminated an office building with a fine soot. Chemical analysis showed PCDDs and PCDFs including the highly toxic tetra isomers. Guinea pigs were chosen as an experimental animal to test the soot's toxicity because of their sensitivity to these compounds, and the liver was examined because it is a target organ. The soot was suspended in 0.75% methyl cellulose and administered in a single dose by gavage at levels of 1,10,100, and 500mgm soot/kgm body weight. Each dose group was composed of 6 males and 6 females. Control groups included 12 (6 male, 6 female) animals fed activated carbon in methyl cellulose, 6 males fed methyl cellulose, and 16 males and 10 females untreated. The guinea pigs were sacrificed at 42 days by suffocation in CO2. Liver samples were immediately immersed and minced in 2% gluteraldehyde in cacadylate buffer at pH 7.4 and 4°C. After overnight fixation, samples were postfixed in 1% OsO4 in cacodylate for 1 hr at room temperature, embedded in epon, sectioned and stained with uranyl acetate and lead citrate.

Glycogen in guinea pig neutrophils: Ultrastructural study of neutrophils at the intradermal site of BCG injection

1983 ◽  
Vol 41 ◽  
pp. 726-727
Author(s):  
Corazon D. Bucana
Keyword(s):  
Bone Marrow ◽  
Guinea Pig ◽  
Electron Density ◽  
Peritoneal Cavity ◽  
Ultrastructural Study ◽  
Guinea Pigs ◽  
Random Distribution ◽  
Glycogen Content ◽  
Polymorphonuclear Neutrophils ◽  
Ultrastructural Studies

In the circulating blood of man and guinea pigs, glycogen occurs primarily in polymorphonuclear neutrophils and platelets. The amount of glycogen in neutrophils increases with time after the cells leave the bone marrow, and the distribution of glycogen in neutrophils changes from an apparently random distribution to large clumps when these cells move out of the circulation to the site of inflammation in the peritoneal cavity. The objective of this study was to further investigate changes in glycogen content and distribution in neutrophils. I chose an intradermal site because it allows study of neutrophils at various stages of extravasation.Initially, osmium ferrocyanide and osmium ferricyanide were used to fix glycogen in the neutrophils for ultrastructural studies. My findings confirmed previous reports that showed that glycogen is well preserved by both these fixatives and that osmium ferricyanide protects glycogen from solubilization by uranyl acetate.I found that osmium ferrocyanide similarly protected glycogen. My studies showed, however, that the electron density of mitochondria and other cytoplasmic organelles was lower in samples fixed with osmium ferrocyanide than in samples fixed with osmium ferricyanide.

Densitometric Identification of Primitive Erythroblasts After Reaction With Diaminobenzidine

1973 ◽  
Vol 31 ◽  
pp. 328-329
Author(s):  
John A. Trotter
Keyword(s):  
Red Blood Cells ◽  
Analytical Method ◽  
Blood Cells ◽  
Guinea Pigs ◽  
Specific Protein ◽  
Visual Examination ◽  
Hemoglobin Synthesis ◽  
Peroxidatic Activity ◽  
Small Density

Hemoglobin is the specific protein of red blood cells. Those cells in which hemoglobin synthesis is initiated are the earliest cells that can presently be considered to be committed to erythropoiesis. In order to identify such early cells electron microscopically, we have made use of the peroxidatic activity of hemoglobin by reacting the marrow of erythropoietically stimulated guinea pigs with diaminobenzidine (DAB). The reaction product appeared as a diffuse and amorphous electron opacity throughout the cytoplasm of reactive cells. The detection of small density increases of such a diffuse nature required an analytical method more sensitive and reliable than the visual examination of micrographs. A procedure was therefore devised for the evaluation of micrographs (negatives) with a densitometer (Weston Photographic Analyzer).

Annulate lamellae in the Sertoli cells of guinea pig testis after unilateral torsion of the spermatic cord

1984 ◽  
Vol 42 ◽  
pp. 196-197
Author(s):  
J. Chakraborty ◽  
A. P. Sinha Hikim ◽  
J. S. Jhunjhunwala
Keyword(s):  
Sertoli Cells ◽  
Guinea Pigs ◽  
Spermatic Cord ◽  
Present Report ◽  
Cell Types ◽  
Annulate Lamellae ◽  
Spermatogenic Cells ◽  
Electron Microscopic ◽  
Structural Details ◽  
First Time

Although the presence of annulate lamellae was noted in many cell types, including the rat spermatogenic cells, this structure was never reported in the Sertoli cells of any rodent species. The present report is based on a part of our project on the effect of torsion of the spermatic cord to the contralateral testis. This paper describes for the first time, the fine structural details of the annulate lamellae in the Sertoli cells of damaged testis from guinea pigs.One side of the spermatic cord of each of six Hartly strain adult guinea pigs was surgically twisted (540°) under pentobarbital anesthesia (1). Four months after induction of torsion, animals were sacrificed, testes were excised and processed for the light and electron microscopic investigations. In the damaged testis, the majority of seminiferous tubule contained a layer of Sertoli cells with occasional spermatogonia (Fig. 1). Nuclei of these Sertoli cells were highly pleomorphic and contained small chromatinic clumps adjacent to the inner aspect of the nuclear envelope (Fig. 2).

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