NONOXIDATIVE METABOLISM OF 2 BUTOXYETHANOL VIA FATTY ACID CONJUGATION IN FISCHER 344 RATS

The influence of training on fatty acid and glyceride synthesis by liver and adipose tissue homogenates of young and old Fischer-344 rats was examined. Four groups of rats (10 animals/group) were studied: young untrained, young trained, old untrained, and old trained. Training of each group was for 10 wk at 75% maximal O2 uptake. Young rats were killed at 6 mo of age and old rats were killed at 27 mo of age. Fatty acid synthesis was assessed by measuring the activities of acetyl-CoA carboxylase, fatty acid synthase, ATP citrate-lyase, "malic" enzyme, and glucose-6-phosphate dehydrogenase. Glyceride synthesis was evaluated by determining the rate of incorporation of [14C]glycerol 3-phosphate into lipids. In addition, lipoprotein lipase activity was measured in acetone-ether powders of adipose tissue from the four groups of rats. In liver, training had no effect on fatty acid or glyceride synthesis in either group. However, aging caused a significant decrease in the activities of four of the lipogenic enzymes but had no effect on glyceride synthesis. Training caused an increase in fatty acid synthase and glyceride synthesis in adipose tissue, and aging decreased lipoprotein lipase activity. It was concluded that training enhances the synthetic capacity of lipids by adipose tissue but that aging had a more profound effect in that the activities of the enzymes involved in these processes were lower in the old rats. Furthermore, the decreased activity of lipoprotein lipase in the older rats may explain the higher plasma triglyceride levels that were observed in these animals.

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Toxic effects of inhaled DMMP on the kidneys of Fischer-344 rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128687 ◽

1987 ◽

Vol 45 ◽

pp. 880-881

Author(s):

D.R. Mattie ◽

C.J. Hixson

Keyword(s):

Left Kidney ◽

Inhalation Exposure ◽

Electron Microscopic Examination ◽

Exposure Period ◽

Male Rats ◽

Continuous Exposure ◽

Fischer 344 Rats ◽

Electron Microscopic ◽

Thin Sections ◽

Fischer 344

Dimethylmethylphosphonate (DMMP) is a simple organophosphate used industrially as a flame retardant and to lower viscosity in polyester and epoxy resins. The military considered the use of DMMP as a nerve gas simulant. Since military use of DMMP involved exposure by inhalation, there was a need for a subchronic inhalation exposure to DMMP to fully investigate its toxic potential.Male Fischer-344 rats were exposed to 25 ppm or 250 ppm DMMP vapor on a continuous basis for 90 days. An equal number of control rats were sham-exposed. Following the 90-day continuous exposure period, 15 male rats were sacrificed from each group. Two rats from each group had the left kidney perfused for electron microscopic examination. The kidneys were perfused from a height of 150 cm water with 1% glutaraldehyde in Sorensen's 0.1M phosphate buffer pH 7.2. An additional kidney was taken from a rat in each group and fixed by immersion in 2.5% glutaraldehyde and 2% paraformaldehyde in 0.1M cacodylate buffer pH 7.4. A portion of the 9 kidneys collected for electron microscopy were processed into Epon 812. Thin sections, stained with uranyl acetate and lead citrate, were examined with a JEOL 100B Transmission Electron Microscope. Microvilli height was measured on photographs of the cells of proximal tubules. This data, along with morphologic features of the cells, allows the proximal convoluted tubules (PCT) to be identified as being S1, S2, or S3 segment PCT.

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Ultrastructure of rat alveolar macrophages activated in situ by poly:IC

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128158 ◽

1987 ◽

Vol 45 ◽

pp. 768-769

Author(s):

A. M. Klinkner ◽

R. A. Weiss ◽

A. Kelley ◽

P. J. Bugelski

Keyword(s):

Venous Blood ◽

Intratracheal Instillation ◽

Buffy Coat ◽

Fischer 344 Rats ◽

Blood Monocytes ◽

Fischer 344 ◽

Polyinosinic:Polycytidylic Acid ◽

Macrophage Activator ◽

Endogenous Peroxidase

Polyinosinic:polycytidylic acid is an inducer of interferon and a macrophage activator. We have found that intratracheal instillation of polyI:C (IT-pI:C) activates rat bronchoalveolar lavage cells (BAL) for a variety of functions. Examination of Giemsa stained, cytocentrifuge preparations showed that IT-pI:C induced a population of BAL not seen in resident BAL. The morphology of these cells suggested that they might be derived from blood monocytes. To test this hypothesis we have examined several populations of macrophages that had been stained for endogenous peroxidase activity as a marker of cells derived from the monocyte-macrophage lineage.Macrophages were obtained from Fischer 344 rats. Peritoneal exudate cells (PEC) were collected by lavage 4 days after i.p. injection of 20 ml 3% thioglycolate. Buffy coat monocytes were separated from venous blood from naive rats.

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