[Differences in the inductive effect of small doses of phenobarbital in rats depending on their age and sex].

The induction influence from low doses of phenobarbital introduced for 3 days (10, 10 and 20 mg/kg) on the detoxication rate of hexanal (100 mg/kg) in mongrel rats of different sexes and age was studied. Investigations included measurements of the protein, phospholipids and glycogen content in the liver and the use of continued lateral position time test. A three-day phenobarbital pre-treatment speeded up the hexenal detoxication in rats of all the age groups except the oldest ones (26--32 months).

[Several biochemical characteristics of rat skeletal musculature during the development under conditions of skeletal muscular loading and hypodynamia].

The weight and biochemistry of the skeletal muscles of rats developing under conditions of the action of the skeletomuscular loads (the I group), under conditions of hypodynamia - at the environmental temperature of 20-22 degrees C (the II group) and at the environmental temperature of 28-30 degrees C (the III group) were studied. Rats of the I group displayed an increase of the mass of the skeletal muscles and also an elevation of protein, glycogen, ATP, creatine phosphate and a decrease of lactic acid content in these muscles. Rats of the III group showed a considerable decrease in the content of enumerated indices both in comparison with indices of control animals and of rats of the I group.

[Retardation of growth and development of rats induced by inhibition of protein synthesis at early postnatal ontogenesis].

Treatment of rats with aurantine for 7-30 days reduces the growth and development of animals, and especially of skeletal muscles. Low relative weight of muscles in aurantine-treated animals was accompanied by low resting and action membrane potentials. Incorporation of labelled uridine and lysine into muscles, heart, brain and liver was decreased.

[Peculiarities of the development of skeletal muscles in physiologically mature and immature mammals].

In one set of experiments, studies have been made on the time during which the membrane potential, action potential, total protein and the content of the dry substance of skeletal muscles of rats and dogs attain the values typical for adult animals. Chronologically, this time is 5-fold shorter in rats, than in dogs. In the other set of experiments, the same indices were studied in physiologically mature (with respect to calendar age) and immature rats and dogs.