Immunohistochemical characterization of telocytes in rat uterus in different reproductive states

Telocytes are a new type of interstitial tissue cells that were recently discovered in the myometrium of nonpregnant uteri and have been suggested to modulate uterine contraction. This work was conducted to extend this research on uteri at different reproductive states and verify whether the morphology and number of telocytes are modified. This study included 24 apparently healthy female albino rats equally classified into four groups: immature rats, adult nonpregnant rats, pregnant rats, and postpartum rats. The middle one-third of the right uterine horns were processed for H and E staining and immunohistochemical detection of telocytes using a c-kit antibody. The count of c-kit-positive telocytes per high-power field in both the endometrium and myometrium was determined and statistically analyzed. C-kit-positive telocytes were detected in the endometrium, mainly around the endometrial glands, and in the myometrium. They were oriented parallel to circular smooth muscles while being located predominately on the boundaries of longitudinal muscle bundles. Immature uteri contained a small number of telocytes in both the endometrium and myometrium that significantly increased in adult nonpregnant uteri. Pregnant uteri showed further significant increase in endometrial telocytes but a significant decrease in myometrial telocytes, possibly to prevent preterm delivery. Postpartum uteri showed the highest count of myometrial telocytes, which could reflect their role in postpartum involution. Telocytes are present in both the endometrium and myometrium of the rat uterus in different reproductive states. Their functions in the endometrium seem to be glandular support and stromal cell communication, whereas in the myometrium they possibly initiate and coordinate myometrial contraction

Can human cord blood-derived stem cells improve statin-induced myopathy in rats? A histological and immunohistochemical study

Primary myopathies of skeletal muscle are diseases with worldwide prevalence for which effective treatment is urgently needed. The aim of this study was to investigate the ability of human umbilical cord blood [HUCB] stem cells to repair damaged skeletal muscle in a rat model of statin-induced myopathy. This study included 24 adult male albino rats divided equally into four groups: the control group; the myopathy group in which myopathy was induced by administration of simvastatin [80 mg/kg/day orally for 6 weeks]; the stem cell-treated myopathy group in which myopathy was induced by administration of simvastatin with subsequent local injection of 1×10[6] HUCB stem cells in the right gastrocnemius; and the untreated myopathy group in which myopathy was induced by administration of simvastatin and then left without treatment for 2 weeks. Specimens of the right gastrocnemius from all rats were prepared, sectioned, and subjected to H and E, Prussian blue, and Masson's trichrome stains in addition to immunohistochemical staining for alpha smooth muscle actin to reveal myofibroblasts. The area% of collagen and muscle fibers and the number of myofibroblasts/high-power field were ascertained. All measurements were statistically analyzed. The gastrocnemius of the myopathy group showed frequent necrotic and damaged muscle fibers, which were replaced by fibrous and fatty tissues. Compared with control rats, there was significant decrease in the area% of muscle fibers and significant increase in the area% of collagen and in the number of myofibroblasts. Two weeks later, there was partial repair of the muscle with no significant differences between stem cell-treated and untreated myopathy groups, which reflects the failure of stem cells to repair damaged myofibers. HUCB stem cells have poor therapeutic effect for myopathy and might be hindered by the complex environment of a severely inflamed and degenerated muscle

Assessment of rat endometrial pinopodes in normal cycles and following HCG ovarian hyperstimulation with or without progesterone supplementation: scanning electron microscopic study

Pinopodes, mushroom-like projections, arise from the endometrial surface at or just before the time of implantation. They have been proposed as a method of identifying endometrial receptivity for transferred embryo in programs of IVF. The present work was planned to assess the expression of pinopodes in rat endometrium in normal cycles and following ovarian hyperstimulation with or without progesterone supplementation as a trial to estimate the optimal date for successful embryo transfer in IVF programs. Forty-five adult female albino rats were divided equally into three groups. In the control group, ovulation was induced by mechanical vagino-cervical stimulation. Group II was subjected to ovarian hyperstimulation using human chorionic gonadotrophin [HCG] 350 IU/kg injected intraperitoneally [two injections 48h apart and vagino-cervical stimulation was performed on the evening of administration of the second injection. Group III was treated in the same way as group II, followed by a daily subcutaneous injection of progesterone 35mg/kg. All rats were sacrificed 3, and 5 days after vagino-cervical stimulation. The middle third of the right uterine horn were processes for scanning electron microscope examination. The mean number of pinopodes was statistically analyzed. In control rats, pinopodes started to appear on day 4 and significantly increased in number on day 5. In the HCG-ovarian hyperstimulated group, there was an early appearance of pinopodes on day 3, which increased in number on day 4 and regressed on day 5. With progesterone supplementation, there was an obvious increase in the number of pinopodes especially on day 4. It could be concluded that ovarian hyperstimulation using HCG may cause early expression of pinopodes and premature formation of an implantation window. Also, progesterone supplementation could enhance endometrial receptivity. This should be taken into consideration in IVF programs to synchronize embryo and endometrial development, which could improve pregnancy rates