[Thyroid hormones and melatonin as means of antioxidant therapy]. / Tireoidnye gormony i melatonin kak sredstva antioksidantnoi terapii.

The possibility of involvement of thyroid hormones and melatonin in cell protection from damage by active oxygen forms (hydroxyperoxide, superoxide radical, and hypochlorite) was investigated. The intensity of inhibition of luminol-dependent chemiluminescence induced by neutrophils and active oxygen forms in the presence of hormones was evaluated. Antioxidant activities of the enzymes were compared with that of glutathione. Probable mechanisms of antioxidant effect of the studied hormones are discussed.

[The mechanisms of the effect of furosemide on the water permeability of the frog bladder and on oxytocin-stimulated contractions of the rat uterus]. / Mekhanizmy vliianiia furosemida na vodnuiu pronitsaemost' mochevogo puzyria liagushki i stimulirovannye oksitotsinom sokrashcheniia matki krysy.

Furosemide increased the hydrosmotic water flow in the frog urinary bladder and promoted the ADH-like effect of inhibitors of phosphodiesterase cAMP, potentiated hydrosmotic effects of theophylline and serosal osmotic hypertonicity but failed to change the effect of pituitrin. Fur reversibly suppressed oxytocin-induced contractions in the rat myometrium, inhibited the activity of the frog urinary bladder PDE cAMP, whereas the activity of the enzyme from the rat medulla and myometrium was activated by saluretic. Incubation of the myometrium strips in Fur resulted in a decrease in the cAMP content of the tissue. The cAMP seems to play an important role both in the myometrium smooth muscle relaxation and in the oxytocin-activated contractions.