Author name:
منهل جبار عبد السعيدي
Supervisor name:
جبار عباس احمد الساعدي | جاسم محمد احمد الكلبي
Abstract:
هنالك علاقة وثيقة بين اعضاء عائلة عوامل نمو بيتا الانتقالية TGF - ? مع توجيه الاحداث المتعلقة بالتكاثر. اجريت الدراسة الحالية في قسم الفسلجة بكلية الطب البيطري في جامعة البصرة خلال المدة بين شهر نيسان، 2013 وكانون الثاني، 2014، لاختبار دور التمنيع ضد وحد | The present study, which has been carried out at the department of physiology, College of Veterinary Medicine, University of Basrah, during the peroid extended from April, 2013 to May, 2014, has been designed to examine the role of immunoneutralization of endogenous inhibin - ?, ?A, and ?B subunits on mammary gland growth and development in primiparous female Wister rats, by evaluating serum growth and differentiation hormones, expression levels of pituitary GH and PRL, and mammary GH - r and PRL - r genes, and immunohistochemical expression of pituitary somatotrophic and lactotrophic cells, and mammary GH and prolactin.Eighty four pregnant female rats were randomly divided into four groups (21 per each). On 5th and 10th day of gestation, control was injected with saline (100?l, i.p.), Ta group was injected with inhibin - ? antiserum (1µg in 100?l of saline, i.p.), Tba group, was injected with inhibin - ?A antiserum (1µg in 100?l of saline, i.p.), and Tbb group was injected with inhibin - ?B antiserum (1µg in 100?l of saline, i.p.). Each group was allocated to 3 equal subgroups : pregnancy, delivery, and lactation subgroups was sacrificed on the 16th day of gestation, on the 1st day after parturition, and the 11th day of lactation, respectively. Body weights of females have been monitored during pregnancy. At parturition and 11th day of lactation, litters weight have been recorded. At the end of each subgroups period, females were anesthetized, dissected and blood samples were obtained for assessment of inhibin - A, - B, activin - A , - B, - AB, GH, and prolactin levels. Pituitary and mammary glangs from each female were removed for evaluation of expression levels of GH, PRL, GH - r, and PRL - r genes using qRT - PCR technique and other samples for histophysiological and immunohistochemical study.The results demonstrate significant increase in cumulative dam weight in Tba group during pregnancy period starting from 8th of gestation compared with control, Ta, Tbb groups. Litters of Ta group at parturition, revealed siginificant higher weight compared with Tba group, and no siginificant difference compared with control and Tbb groups. Litter of Tba group recorded a highest siginificant weight gain among experimental groups.Serum inhibin - A in Tbb group during pregnancy, recorded higher level among experimental groups. During delivery, the higher significant level has been registered in control and Tbb groups. During lactation, no siginificant difference has been recorded between groups. In comparison between periods, the level in control during delivery showed the higher level compared with pregnancy and lactation periods, whereas Ta and Tba groups recorded no difference between periods, while Tbb group showed significantly higher level during pregnancy and decreased during delivery and lactation. Inhibin - B during pregnancy in control females recorded the highest level among the experimental groups. During delivery, higher levels have been recorded in control and Tba groups. At lactation, there is no siginificant difference between Ta, Tba, and Tbb groups but they were significantly higher than control. In comparison between periods, the concentration in control during pregnancy recorded higher level than other periods. Ta, Tba, and Tbb groups recorded no siginificant differences between pregnancy and delivery periods but they were significantly higher in lactation period.Activin - A concentration during pregnancy and delivery in Tbb was higher among experimental groups. During lactation, there is no difference between experimental groups. In comparison between periods, all groups showed higher levels at delivery. Activin - B during pregnancy and delivery in Tbb group recorded the lowest concentration. During lactation, no differences has been shown between groups. In comparison between periods, the levels in all groups was higher at lactation followed by pregnancy period and delivery periods. Activin - AB concentration in control and Ta groups were higher during pregnancy and delivery periods, while no siginificancy was recorded during lactation. In comparison between periods, all groups showed higher levels at lactation period followed by pregnancy and delivery periods.Serum GH in Ta group during pregnancy recorded higher level among groups During delivery, the higher level has been recorded in Ta and Tba groups. During lactation, the higher level has been recorded by Ta group among groups. In comparison between periods, the levels in all groups were higher at delivery followed by pregnancy and lactation. Serum prolactin during pregnant, delivery, and lactation showed no siginificant difference between experimental groups. In comparison between periods, the levels in all groups showed higher levels at delivery followed by lactation and pregnancy.Result of pituitary GH gene expression levels in Ta and Tba groups increased significantly compared with Tbb in all of studied periods.Result of pituitary PRL gene expression levels during pregnancy increased siginificantly in Tba group among experimental groups. During delivery, the fold changes in Ta and Tba groups showed no significant difference between each other, but they were significantly higher than Tbb group. At lactation period, there is no siginificant difference between groups.Result of mammary GH - r gene expression levels during pregnancy and delivery registered siginificant elevation in Ta, whereas lactation period showed no siginificant difference between groups. Mammary PRL - r gene expression levels during pregnancy was higher in Tbb group, whereas delivery and lactation showed siginificant elevation in Ta and Tba groups.Expression of pituitary somatotrophic cells during pregnancy showed significant higher score (number of positive stained cells and intensity of staining) in Ta group among the experimental groups. At delivery and lactation, scores of Ta and Tba groups, increased significantly. In comparison between periods, in all groups, higher score has been shown at delivery, whereas the lowest score recorded at lactation. Expression of pituitary lactotrophic cells during each periods showed no difference between groups. In comparison between periods, in all experimental groups, higher score of staining was recorded at delivery and lowest score recorded at pregnancy.Expression of mammary GH during pregnancy showed significant higher score in Ta group among the experimental groups. At delivery, the score of Ta group increased siginificantly. At lactation, Ta and Tbb groups registreted no siginificant difference between them, whereas they were siginificant higher than control and Tba groups. In comparison between periods, in all groups, higher scores have been shown at parturition and the lowest at lactation. Expression of mammary PRL during pregnancy and lactation revealed no siginificant difference between experimental groups. In comparison between periods, in all experimental groups, higher score of staining has been shown at delivery, whereas the lowest score recorded at pregnancy.Histological findings in treated groups, pituitary sections reveals progress in the morphological appearance of secretory cells which appeared larger and contains profuse cytoplasmic secretory granules. Ta females reveals more proliferation and cytoplasmic secretory granules. These differences continued at delivery and retarded at lactation. Mammary glands of treated groups at pregnancy showed marked development in alveolar morphogenesis. At delivery, Ta and Tbb females showed high number of lobules and alveoli. Lactation period showed well - developed vacuolated epithelial cells.In conclusion, passive immunization against inhibin - ?, ?A, subunits but not ?B subunit, at 5th and 10th day of pregnancy, have potent role in mammary gland growth and development in primiparous female Wister rats.
