Effect of Dydrogesterone on the Oxytocin Reactivity of Venous Blood Neutrophils in Pregnant Women and Puerperae

Abstract

The ability of steroid hormones to modulate the binding of oxytocin to oxytocin receptors is of great interest. The purpose of this article was to study the effect of oxytocin, dydrogesterone and their mixture on the radical activity of venous blood neutrophils in pregnant women during the 3rd trimester of a normal pregnancy and in women on the 1st day after term delivery. Materials and methods. Using the chemiluminescent method (BChL-07 biochemiluminometer) and cell stimulation with latex particles, we studied non-genomic and genomic effects of dydrogesterone (5∙10–5 g/l), oxytocin (10–7 IU/l) and their mixture on the radical activity of venous blood neutrophils in 20 pregnant women in the 3rd trimester of a normal pregnancy and 10 women on the 1st day after term labour. When the noise level was automatically subtracted, the following were recorded: maximum intensity of the synthesis of reactive oxygen species, time to reach the maximum of synthesis intensity, and area under the chemiluminogram curve, reflecting the total synthesis of radical particles over the course of 30 min. Results. Baseline radical activity of neutrophils in women on the 1st day after term delivery was found to be three times higher than in women during the 3rd trimester of a normal pregnancy. Judging by the area under the chemiluminogram curve and maximum intensity of the synthesis of reactive oxygen species, oxytocin had an equal stimulating effect on venous blood neutrophils both in pregnant women during the 3rd trimester and in puerperae. Dydrogesterone in each group of women equally stimulated the radical activity of neutrophils, both non-genomically and genomically. In both groups, under the action of dydrogesterone through membrane receptors, oxytocin reactivity of neutrophils remained unchanged, while through nuclear receptors, it decreased. Possible mechanisms of progesterone’s involvement in the regulation of oxytocin reactivity of the myometrium and venous blood neutrophils in women during pregnancy and postpartum are considered.