Erythrocyte vitamin B2 and B6 dependent enzymes in adult and newborn Thoroughbred horses

Com o propósito de determinar o estado nutricional de cavalos Puro-Sangue Inglês (PSI) em relaçäo à riboflavina (vitamina B2) e à piridoxina (vitamina B6), 10 animais adultos e 30 recém-nascidos foram investigados. Foi observado um bom estado nutricional quanto à riboflavina, notando-se moderada deficiência de piridoxina nos animais adultos, mas näo nos recém-nascidos. Estes fatos sugerem que os animais adultos devam receber suplementaçäo com piridoxina

The special behavior of equine erythrocytes connected with the methemoglobin regulation.

Erythrocytes from thoroughbred horses were submitted to total (80-90%) and partial (25-40%) oxidation of hemoglobin by sodium nitrite. The ability of these cells to reduce methemoglobin to hemoglobin in the presence of either glucose, glucose plus methylene blue or lactate was investigated. The results were compared with those ones obtained for human erythrocytes. Under total oxidation: the horse erythrocytes need longer incubation time with glucose or glucose plus methylene blue than human erythrocytes for reducing the methemoglobin; methylene blue did not enhance methemoglobin reduction in the equine erythrocytes, as occurred in human erythrocytes; for horses, lactate was a more efficient substrate in promoting methemoglobin reduction. The reduction of methemoglobin by equine erythrocytes under partial oxidation was very quick in any of the incubation media. The results can explain the incongruity between the previously reported inability of equine erythrocytes to reduce methemoglobin and the lack of methemoglobinemias in equine veterinary practice.

Estudo histoquimico do glicogenio e lipidios no musculo cardiaco do rato albino durante o estresse agudo. / Histochemical study of glycogen and lipids in cardiac muscle of albino rats during acute stress

Foi realizado o estudo histoquimico do glicogenio e lipidios no coracao do rato albino em estresse agudo provocado pelo formol. Foram utilizados 12 animais, 6 constituiram o "grupo controle e 6, submetidos ao estresse agudo, o "grupo experimental". O glicogenio foi estudado pela tecnica do PAS com controle pela amilase salivar. O grau de positividade desta substancia foi o mesmo em ambos os grupos.Os lipides em geral foram estudados pela tecnica do "sudan black B". Importante aumento do grau de positividade desta substancia foi encontrado na fibra muscular cardiaca dos ratos em estresse agudo. A tecnica do sulfato de azul de Nilo mostrou, nestes lipidios, predominancia de radicais acidos

Maternal and fetal liver enzymes of mid-to-term pregnant rats chronically treated with magnesium sulphate.

1. Pregnant rats were injected daily with 150 mg/kg body weight magnesium sulphate (MgSO4) starting at the 5th day of gestation and sacrificed at the 13th, 15th, 19th or 21st day of pregnancy. 2. Maternal liver enzymes of glycolysis (HK, PFK, PK, LDH), pentose shunt pathway (G-6-PD) and glutamate metabolism (Ala-T, Asp-T) were unaltered by the treatment. 3. Fetal liver PK, LDH, G-6-PD, Ala-T and Asp-T activities were strongly activated by MgSO4 to levels in some instances as high or even higher than those found in the adult rat liver. 4. Results support recent evidence that MgSO4 induces precocious maturation of certain morphofunctional features of the fetal rat liver. 5. Data presented herein cannot account for the strong deleterious effects of the drug on rat pregnancy. Instead, such effects would be better explained by the direct cell toxicity of MgSO4.

Atividade de algumas enzimas do musculo cardíaco do rato albino durante o estresse agudo. Estudo histoquímico / Activity of some enzymes of cardiac muscle of albino rats during acute stress. Histochemical study

Foram estudadas as alteracoes histoquimicas relativas ao grau de positividade da desidrogenase succinica, da desidrogenase lactica, da adenosina trifosfatase e da aldolase da fibra cardiaca do rato albino em estresse agudo. Os resultados obtidos indicam que, durante o estresse agudo, ha maior demanda metabolica da fibra cardiaca com aumento do metabolismo oxidativo aerobico, nao ocorrendo hipoxia

Patterns of mid-to-term placental enzymes in rats treated with magnesium sulphate.

1. Pregnant rats were injected daily with 150 mg/kg b.w. of magnesium sulphate (MgSO4) starting at the 5th day gestation and sacrificed at the 13th, 15th, 19th or the 21st day of pregnancy. 2. The profiles of LDH, G-6-PD, HK and Ala-T activities in mid-to-term placentae were not changed by the drug. 3. Placental PK was strongly activated by MgSO4 in 13-19 day pregnant rats, whereas Asp-T was more severely depressed at the final phase of pregnancy. 4. Although mild to moderate changes in the flow of substrates should be predictable by the results, it seems unlikely that these could account for the reported deleterious effects of MgSO4 on rat offsprings.

Energy metabolism in the erythrocytes of thoroughbred horses connected with perinatal physiological hemolysis.

1. The metabolism in the erythrocytes of thoroughbred horses in a sequential study from umbilical cord to the 1st month was investigated. 2. Emphasis was put on hemolytic period at which: (a). PFK, GSH-Px and GSH play a significant role. (b). There is a lower glucose consumption determined by a decreased activity in several enzymatic steps. (c). Singularly high concentrations of 2-3DPG and ATP were detected. 3. It has been suggested that the metabolic adjustments were achieved by an increased activity of the hexose monophosphate shunt, G-3PD and AK.

[Some ultrastructural aspects of the cardiac muscle of albino rat during the acute stress produced by formaldehyde (author's transl)]. / Alguns aspectos ultra-estruturais da fibra muscular cardíaca do rato albino sob a influéncia do "stress" agudo provocado pelo formol.

The authors studied ultrastructurally the influence acute stress, produced by formaldehyde, has on some aspects of the cardiac muscle metabolism in albino rats. The results showed that the cardiac muscle was induced to develop additional work, represented ultrastructurally by an increase in the number of lipid droplets and increased concentration and volume of mitochondria.

Histochemical (polysaccharides, proteins, nucleic acids and enzymes) and autoradiographic (incorporation of 35S labelled sodium sulfate) study of the epithelial intestinal cells of Xenodon merremii Wagler, 1824 (Ophidia).

A histochemical and autoradiographic study of the lining intestinal epithelium of the snake Xenodon merremii is reported. The absorptive cells present neutral polysaccharides, arginine, tyrosine, tryptophan, cysteine, alkaline phosphatase, acid phosphatase, ATPase, AMPase, esterase and RNA. There are histochemical differences between the goblet cells of the small and of the large intestine. Whereas in the former predominates the neutral polysaccharides and are found arginine, tyrosine, tryptophan and cysteine, in the latter predominates the sulfated polysaccharides (confirmed by the uptake of radioactive sulfur) and no amino acids were found.