Additional studies on the effects of neonatal thymectomy and lactate dehydrogenase virus infection on mice

Zusammenfassung Die gegebenen Befunde lassen vermuten, dass neonatale Thymektomie und/oder Infektion mit LDH-Virus einen Effekt auf eine Anzahl von Faktoren wie LDH-Plasma-Spiegel, Gewichtserhöhung und Lebensdauer in Mäusen hervorrufen können. Der Virustiter im Plasma ist vom Zeitpunkt der Infektion abhängig.

---

---

Supported by Public Health Service research grant No. 5 R01 CA05742-06 from the National Cancer Institute.     

Effect of actinomycin D on mice infected with the lactate dehydrogenase virus

Résumé Chez la souris traitée avec de l'actinomycine d, 1 h après injection de virus LDH, la quantité de l'enzyme LDH dans le plasma sanguin et le taux de virus sont élevés. Ces résultats sont discutés au point de vue d'une inhibition possible d'interferone et du mechanisme responsable de l'augmentation de la quantité de l'enzyme LDH.

---

---

Supported by Public Health Service research grant No. 5 R01 CA05742-05 from the National Cancer Institute.

---

I am indebted to MissIris Carter for her technical assistance.     

Additional studies on the effect of the lactate dehydrogenase virus on murine sex ratios

Résumé On met en évidence le fait que le virus LDH exerce un effet sur la proportion des sexes chez les souris par l'intermédiaire du père. En ce qui concerne le mécanisme impliqué dans ce phénomène, les résultats obtenus jusqu'à présent semblent insuffisants pour permettre une conclusion.

---

---

Supported by a grant from the Maryland Division of the American Cancer Society.     

Strain influence on the immune response of mice to the friend virus

Résumé La méthode d'Immunoélectroadsorption a permis de déceler la présence d'anticorps contre le virus de Friend, non seulement dans les souches de souris résistantes, mais aussi dans les souches sensibles à ce virus.     

Age-dependent response of lactate dehydrogenase of pituitary of rat to testosterone

Summary The effects of time and various doses of testosterone on the responsiveness of lactate dehydrogenase of pituitary of 7-, 38- and 78-week-old rats were studied. The activity of the enzyme increases in 78-week-old rats. Castration decreases the enzyme activity at all ages. Maximum increase in the enzyme activity is seen with 50 and 100 g of testosterone 4 h after administration of hormone to castrated rats. No further time and dose-dependent effect is observed. The magnitude of increase for the enzyme is higher at the age of 38 weeks and decreases in 78-week-old rats.To whom all correspondence should be addressed. The authors are grateful to Professor M.S. Kanungo, Biochemistry Laboratory, Department of Zoology, Banaras Hindu University for the suggestions and encouragement. K.V.G. thanks the PL-480 for a research fellowship.     

Sex difference in susceptibility of mice to pneumococcus

Résumé L'injection deDiplococcus pneumoniae (type 12) par voie intrapéritonéale à des souris albinos provoque un taux de mortalité significativement plus élevé chez les mâles que chez les femelles. Ce fait pourrait servir de modèle à l'étude des différences sexuelles dans la résistance à l'infection.     

Ambiquitous behavior of rabbit liver lactate dehydrogenase

Summary Rabbit liver mitochondrial fraction shows lactate dehydrogenase activity. The enzyme can be released from particles by increasing the pH and the ionic strength of the medium. There is a narrow range of pH (6.8–7.4) and ionic strength (20–50 mM NaCl) in which the solubilization sharply increases. It has been shown that divalent anions (SO ₄ ^2– ) and cations (Mg²⁺, Ca²⁺) are highly effective specific solubilizing agents. NADH (1.5 mM) and ATP (1.0 mM) were effective in solubilizing 50% of the enzyme bound, whereas the same concentrations of the analogs NAD⁺ and ADP had little effect. Cytosolic lactate dehydrogenase bound to the mitochondrial fraction and a saturation of particles by enzyme was observed in all experiments performed. The in vitro binding requires a short period of incubation between the enzyme and particles and the binding is independent of the temperature in the 0–37°C range. Binding was prevented by 0.15 M NaCl. The bound enzyme is approximately 20% less active than the soluble one. The results described give support to the proposal that rabbit liver lactate dehydrogenase has an ambiquitous behavior, like other glycolytic enzymes, which have not a fixed intracellular localization.     

Ambiquitous behavior of rabbit liver lactate dehydrogenase

Rabbit liver mitochondrial fraction shows lactate dehydrogenase activity. The enzyme can be released from particles by increasing the pH and the ionic strength of the medium. There is a narrow range of pH (6.8-7.4) and ionic strength (20-50 mM NaCl) in which the solubilization sharply increases. It has been shown that divalent anions (SO4(2-) and cations (Mg2+, Ca2+) are highly effective specific solubilizing agents. NADH (1.5 mM) and ATP (1.0 mM) were effective in solubilizing 50% of the enzyme bound, whereas the same concentrations of the analogs NAD+ and ADP had little effect. Cytosolic lactate dehydrogenase bound to the mitochondrial fraction and a saturation of particles by enzyme was observed in all experiments performed. The in vitro binding requires a short period of incubation between the enzyme and particles and the binding is independent of the temperature in the 0-37 degrees C range. Binding was prevented by 0.15 M NaCl. The bound enzyme is approximately 20% less active than the soluble one. The results described give support to the proposal that rabbit liver lactate dehydrogenase has an ambiquitous behavior, like other glycolytic enzymes, which have not a fixed intracellular localization.     

Multiple lactate dehydrogenase alleles in the LizardAgama stellio

Zusammenfassung Es wurde das gehäufte, geographisch begrenzte Auftreten multipler Allele für LDH-H, das bei den bisher untersuchten Organismen nur selten Varianten zeigt, nachgewiesen. Ebenso gelang die Identifizierung von elektrophoretischen Varianten in Abhängigkeit vom pH.     

X-irradiation of mice in early fetal period influences dose-dependently sex ratio of offspring until weaning

Summary Fractionated X-irradiation of mouse fetuses on gestation days 11–13 resulted in a significantly increased postnatal mortality of female litters. This occurred only at 3×110 rad, which was the threshold for the formation of typical neuroepithelial, rosette-like malformations.We are greatly indebted for the technical assistance of Miss C. Gutmann, Mrs I. Hempfling and Mrs K. Pfaff.     

X-irradiation of mice in early fetal period influences dose-dependently sex ratio of offspring until weaning.

Fractionated X-irradiation of mouse fetuses on gestation days 11-13 resulted in a significantly increased postnatal mortality of female litters. This occurred only at 3 x 110 rad, which was the threshold for the formation of typical neuroepithelial, rosette-like malformations.