Jale Öner

Distributions of PCNA and Cas-3 in rat uterus during early pregnancy.

The aim of present study was to determine the distributions of proliferating cell nuclear agent (PCNA) and Cas-pase-3 (Cas-3) and their possible roles in implantation and decidualization during early pregnancy at immunohistochemical level. The tissue samples from pregnant animals between gestational days 1-5 were incubated by PCNA and Cas-3 antibodies and the obtained results were evaluated quantitatively. It was observed that PCNA immunoreactivity in uterine luminal epithelium and glandular epithelium reduced as from day 2 of gestation and disappeared as from day 4 of gestation. PCNA staining intensity in stromal cells and myometrium increased gradually with progressing gestation. While Cas-3 immunoreactivity was strongly detected in luminal and glandular epithelium throughout the whole gestational period, its reactivity markedly increased as from day 3 of gestation. In conclusion, it may suggest that the blastocyst implantation induces the uterine luminal epithelial cell death and stromal cell proliferation around the embryo in the uterus.

The effect of pinealectomy and leptin hormone on the proliferation and apoptosis activation in Syrian hamster testis in different photoperiods

The effects of pinealectomy and leptin hormone on proliferative and apoptotic processes in the epithelia of testicular seminiferous tubules of Syrian hamsters have been investigated. Proliferative and apoptotic processes were assessed semi-quantitatively by proliferating cell nuclear antigen (PCNA) and caspase-3 immune stainings. Animals used in the study were divided into four groups; control, pinealectomy (PinX), leptin-treated (10 microg/mL/day/kg body weight, intraperitoneally) and pinealectomy + leptin groups. Half of the hamsters in each group were exposed to short and the other half to long photoperiods for 8 weeks. In short photoperiod, PCNA activity especially in spermatogonia was significantly higher in the pinealectomy and leptin-treated groups compared with the control group. Histological score (HSCORE) value of PCNA in the PinX + leptin group was lower than those of PinX and leptin-treated groups. HSCORE value of caspase-3 in PinX and PinX + leptin groups was increased. In the long photoperiod, PCNA activation in the PinX group was significantly lower than the control group while the differences between the controls and other groups were not significant. The difference between the increases in caspase-3 activity in the PinX and control groups was significant. Thus, it was observed that photoperiods had no effect on the proliferation activity in the control groups. The inhibiting effect of short photoperiod on testis was not observed throughout 8 weeks. PinX eliminated the inhibiting effect of short photoperiod but did not alter the stimulating effect of long photoperiod. Leptin did not show any effect in long photoperiod but decreased proliferation by stimulating melatonin in short photoperiod.

The Effects of Triiodothyronine on Rat Testis: A Morphometric and Immunohistochemical Study

The aim of present study was to investigate the effects of 3,3′,5-triiodothyronine (T3) on rat testis both morphometrically and immunohistochemically with determining of insulin-like growth factor I (IGF-I) expression. Adult male Wistar-albino rats used in the study were divided into two groups; control and T3-treated groups. After T3 treatment there was observed to be a decrease in testicular weights, diameters of seminiferous tubules and the number of sertoli cells, and an increase in the number of leydig cells (P<0.05). Some of the seminiferous tubule lumens of T3 administrated rats had cellular debris. IGF-I was localized in sertoli cells, late spermatids and leydig cells of all groups. IGF-I immunoreactivity in T3 treated rats was higher than in controls in all stages of the cycle of rat seminiferous epithelium, but the staining intensity of leydig cells were similar in both groups. In conclusion, the present results suggest that T3 may modulate the testicular function by affecting IGF-I activity at the gonadal level.

Effects of Melatonin on Skeletal Muscle of Rats with Experimental Hyperthyroidism

The aim of this study was to investigate structural changes that occurred in the skeletal muscle of rats with experimental hyperthyroidism and the effect of melatonin on these changes. Groups of animals were designated as controls, 3,3′,5‐triiodothyronine (T3) injected and T3 + melatonin injected group. At the end of the study the tissue specimens were harvested and their structure examined. In the skeletal muscle of T3 injected rats a decrease was observed in muscle fiber diameter, splitting of fiber, collections of adipose tissue in perimysium, and gathering of nuclei in central compared to the control. Electron microscopic examination showed that mitochondria were dilated and the I band was less clear. In the T3 + melatonin injected group, the structure of fibers was similar to control. In conclusion, this study showed that T3 injection caused structural changes in the skeletal muscle and that melatonin had a positive effect on these changes.