Influence of maternal dexamethasone treatment on morphometric characteristics of pituitary GH cells and body weight in near-term rat fetuses.

Growth hormone (GH) and glucocorticoids have a powerful influence on controlling fetal growth, differentiation and maturation of numerous tissues. In the present study, the effect of maternal dexamethasone (Dx) treatment on GH cells and body weight in 19- and 21-day-old rat fetuses was investigated using immunocytochemical and morphometric methods. Pregnant female rats received daily injections of 1.0-0.5-0.5 mg Dx/kg b.w. on days 16-18 of pregnancy (experimental group), while the control group received an equal volume of saline. Dx treatment of pregnant rats enhanced immunostaining intensity and significantly increased (

Multiple dexamethasone treatment affects morphometric parameters of gonadotrophic cells in adult female rats.

Exposure to glucocorticoids leads to numerous changes in various biological systems including the reproductive system. The aim of the present work was to find out whether dexamethasone (Dx) treatment of adult female rats would influence the histological and morphometric characteristics of the pituitary gonadotrophic cells (luteinizing--LH cells and follicle stimulating--FSH cells). One group of female Wistar rats received Dx injections on three consecutive days in doses 1.0, 0.5 and 0.5 mg/kg b.w. respectively, while the control rats were treated with equivalent volumes of saline. Experimental and control animals were sacrificed 24 h and 72 h after the last injection. The peroxidase-antiperoxidase (PAP) immunocytochemical procedure was used to study the LH and FSH cells. The stereological and morphometric analyses showed that multiple Dx treatments of female rats significantly decreased the volume of LH cells and the volume of their nuclei 24 h and 72 h after the last Dx injection in comparison with control values. At 24 h after Dx treatment, the volume density of LH cells was significantly increased, but at 72 h differences between the experimental and control groups were insignificant. The increase in number of LH cells per unit area (mm2) was significant at both timepoints (24 h and 72 h). Stereologic and morphometric characteristics of FSH cells was changed after Dx treatment in the same manner as that of LH cells, except for the volume density, where a significant increase was established 24 h and 72 h after the last Dx application. These results clearly demonstrate that 24 h and 72 h after the last of three Dx injections there were changes in the immunocytochemical and morphometric features of gonadotrophic cells

Influence of maternal dexamethasone treatment on morphometric characteristics of pituitary GH cells and body weight in near-term rat fetuses.

Growth hormone (GH) and glucocorticoids have a powerful influence on controlling fetal growth, differentiation and maturation of numerous tissues. In the present study, the effect of maternal dexamethasone (Dx) treatment on GH cells and body weight in 19- and 21-day-old rat fetuses was investigated using immunocytochemical and morphometric methods. Pregnant female rats received daily injections of 1.0-0.5-0.5 mg Dx/kg b.w. on days 16-18 of pregnancy (experimental group), while the control group received an equal volume of saline. Dx treatment of pregnant rats enhanced immunostaining intensity and significantly increased (p<0.05) GH nuclear and cell volume, as well as volume density and number of GH cells per square millimeter in 19-day-old fetuses compared to the controls. In 21-day-old fetuses after maternal Dx administration, immunoreactivity, volume density and number of GH cells remained significantly increased (p<0.05). Dx treatment of pregnant rats resulted in marked body weight reduction of 21-day-old but not 19 days old fetuses in comparison with the corresponding controls. The presented results demonstrate that maternal Dx application has pronounced effect on morphometric parameters of GH cells of 19- and 21-day-old fetuses. Also, in near-term rat fetuses body weight was largely independent of pituitary GH cell activity