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  • Author or Editor: Yoshimitsu Maede x
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Summary

The hemolytic effect of onion consumption in dogs with hereditary high erythrocyte reduced glutathione and potassium concentrations (designated HK dogs) was compared with that in clinically normal dogs. Twelve hours after oral administration of boiled onions (200 g/dog), hemoglobin concentration decreased to 84.4% of the initial value in hk dogs; it decreased only to 90.5% in clinically normal dogs. At 24 hours, methemoglobin concentration was significantly (P< 0.05) higher in HK dogs than in clinically normal dogs. The concentration of erythrocyte oxidized glutathione increased about fivefold at 10 hours in HK dogs, whereas it did not change during the experimental period in clinically normal dogs. In addition, at 12 hours, the proportion of erythrocytes containing Heinz bodies increased to 24.4% in hk dogs, but increased only to 1.2% in clinically normal dogs. Thus, results indicated that HK dogs were more susceptible to the oxidant action of onions than were clinically normal dogs.

Free access
in American Journal of Veterinary Research

Summary

To clarify the oxidant defense functions of reduced glutathione (gsh) in erythrocytes, the effect of gsh deficiency on in vitro oxidant defense was studied, using gsh-deficient sheep erythrocytes (low-gsh cells). The formation of Heinz bodies in low-gsh cells was higher than that in high-gsh cells when the cells were incubated with an oxidant drug, acetylphenylhydrazine (aph). Artificial depletion of gsh by 1-chloro-2,4-dinitrobenzene in high-gsh cells resulted in increased Heinz body formation in these cells incubated with aph. Furthermore, high negative correlation was observed between Heinz body formation and gsh content in sheep erythrocytes exposed to aph. These results clearly indicate that erythrocyte gsh is indispensable for erythrocyte defense against oxidative damage induced by aph, and support the previous observations that sheep with low-gsh erythrocytes were more susceptible to oxidative agents than were sheep with high-gsh erythrocytes.

Free access
in American Journal of Veterinary Research

Summary

The cause of species difference in the susceptibility of erythrocytes to L-sorbose, and the difference in the hemolytic effect of sorbose on high potassium-containing (hk) and low potassium-containing (lk) canine erythrocytes were examined. L-Sorbose was phosphorylated in canine erythrocytes, but not in human erythrocytes. Furthermore, sorbose-1-phosphate, a metabolite of L-sorbose, strongly inhibited the hexokinase of lk canine erythrocytes, but not that of hk canine erythrocytes. These results strongly indicated that inhibition of hexokinase by sorbose-1-phosphate in lk erythrocytes induced severe glycolytic limitation in these cells, resulting in hemolysis, and that hk erythrocytes are resistant to sorbose-induced hemolysis because these cells have a high hexokinase activity.

Free access
in American Journal of Veterinary Research

Summary

Although the cation composition of mature erythrocytes in clinically normal dogs comprises low K concentration and high Na concentration because of lack of a Na/K pump, a dog was found that had erythrocytes with high K and reduced glutathione (gsh) concentrations attributable to the existence of a Na/K pump (hk/hg cells). However, 2 dogs were subsequently found that had erythrocytes with high K concentration and increased Na/K pump activity, but without high gsh accumulation (hk/lg cells). In those hk/lg cells, Na-dependent glutamate and aspartate influxes were about a sixth of the values in hk/hg cells, despite a steep Na gradient, and cellular glutamate concentration was not accumulated in hk/lg cells as it was in hk/hg cells. In the latter cells, glutamate and aspartate accumulated because of high activity of Na-dependent amino acid influxes. Therefore, low concentration of glutamate may be the reason for the low gsh concentration in hk/lg cells. In such cells, however, aspartate and glutamine were accumulated similarly as they were in hk/hg cells. The hk/lg cells also had a defect in amino acid metabolism. This defect was different from that in hk/hg cells. Thus, hk/lg cells might be a new model for study of defects in amino acid transport and amino acid metabolism.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To determine the usefulness of canine RBC with high concentrations of potassium, reduced glutathione (GSH), and amino acid(ie, HK cells) for in vitro cultivation of Babesia gibsoni.

Animals—RBC were obtained from 3 dogs that had inherited HK cells and from 3 genetically unaffected dogs that, therefore, had RBC with lower potassium (LK) concentrations (ie, LK cells).

Procedures—First, B gibsoni were cultivated using HK or LK cells in alpha-modification of Eagle medium, consisting of Earle salts with glutamine and without ribosides, deoxyribosides, and sodium bicarbonate under a humidified atmosphere containing 5% CO2 at 37 C. Second, parasites were cultivated with LK- or HK-cell lysates. Finally, HK cells were separated into 3 fractions (bottom, middle, top layers) by density gradient centrifugation, and B gibsoni were cultivated with each of the HK-cell fractions. In addition, the concentrations of free amino acids and reduced glutathione (GSH) in each HK-cell fraction were measured.

ResultsB gibsoni preferentially multiplied in HK-cell cultures rather than in LK-cell cultures. Furthermore, the addition of HK-cell lysate to the culture medium resulted in enhanced multiplication of the parasites. Higher multiplication of the parasites was observed in HK cells from the top layer, compared with HK cells from the middle and bottom layers. The HK cells from the top layer had higher concentrations of glutamate, aspartate, and GSH, compared with HK cells from the middle and bottom layer.

Conclusions—Canine HK cells are useful host cells for in vitro cultivation of B gibsoni, and the high concentrations of glutamate, aspartate, and GSH may result in enhancement of multiplication of the parasites in HK cells. (Am J Vet Res 2000;61:1520–1524)

Full access
in American Journal of Veterinary Research

Summary

Twenty-seven wild geese (Anser albifrons) suffering from lead poisoning caused by ingestion of lead shot were treated with disodium calcium ethylenediaminetetraacetate. The concentration of lead in blood ranged from 0.4 to 23.0 μg/ml, with a mean concentration of 5.6 μg/ml. In 22 of the birds, 1 to 48 lead pellets (mean, 10.5 pellets/bird) were seen on radiographs of their gizzards. Eleven of 27 birds recovered 3 to 8 weeks after the initiation of treatment. In the birds that recovered, the lead pellets were rapidly eroded as the birds recovered their appetites in response to treatment, and disappeared radiographically between treatment days 17 and 52. The birds that did not survive died within 4 weeks, despite decreased concentrations of lead in blood. Of these 16 birds, 15 had radiographic evidence of impaction of the proventriculus at the first examination and no evidence of resolution of the impaction at the time of death. In contrast, only 2 of the 11 geese that recovered had impaction of the proventriculus at the time of admission. Thus, the condition of the proventriculus seems to be the first consideration to evaluate in the prognosis of lead poisoning in geese.

Free access
in Journal of the American Veterinary Medical Association

Abstract

Objective—To determine whether dogs given garlic extract developed hemolytic anemia and to establish the hematologic characteristics induced experimentally by intragastric administration of garlic extract.

Animals—8 healthy adult mixed-breed dogs.

Procedure—4 dogs were given 1.25 ml of garlic extract/kg of body weight (5 g of whole garlic/kg) intragastrically once a day for 7 days. The remaining 4 contol dogs received water instead of garlic extract. Complete blood counts were performed, and methemoglobin and erythrocyte-reduced glutathione concentrations, percentage of erythrocytes with Heinz bodies, and percentage of eccentrocytes were determined before and for 30 days after administration of the first dose of garlic extract. Ultrastructural analysis of eccentrocytes was performed.

Results—Compared with initial values, erythrocyte count, Hct, and hemoglobin concentration decreased to a minimum value on days 9 to 11 in dogs given garlic extract. Heinz body formation, an increase in erythrocyte- reduced glutathione concentration, and eccentrocytes were also detected in these dogs. However, no dog developed hemolytic anemia.

Conclusions and Clinical Relevance—The constituents of garlic have the potential to oxidize erythrocyte membranes and hemoglobin, inducing hemolysis associated with the appearance of eccentrocytes in dogs. Thus, foods containing garlic should not be fed to dogs. Eccentrocytosis appears to be a major diagnostic feature of garlic-induced hemolysis in dogs. (Am J Vet Res 2000;61:1446–1450)

Full access
in American Journal of Veterinary Research