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Mary-catherine Madekurozwa - One of the best experts on this subject based on the ideXlab platform.
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Immunohistochemical localization of the progesterone and oestrogen receptors in the shell Gland of sexually immature ostriches (Struthio camelus) with active or inactive ovaries.
Research in veterinary science, 2004Co-Authors: Mary-catherine MadekurozwaAbstract:The immunohistochemical localization of progesterone and oestrogen receptors was studied in the shell Gland of the immature ostrich (Struthio camelus) during periods of ovarian activity and inactivity. In birds with active ovaries moderate to strong immunostaining for the progesterone receptor was observed in the surface epithelium and Tubular Glands. In contrast faint progesterone receptor immunostaining was observed in the surface epithelium of the shell Gland in ostriches with inactive ovaries. In addition, bud-like invaginations of the surface epithelium, which signaled Tubular Gland development, were negative for the progesterone receptor. Oestrogen receptor immunostaining, which was seen only in birds with active ovaries, was weak and restricted to nuclei of the surface epithelium. These results suggest that steroid hormones secreted by the active ovary regulate the differentiation of the shell Gland. Furthermore, the influence of these hormones on the shell Gland appears to be mediated predominantly through the activation of the progesterone receptor.
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A Study of the Immunohistochemical Localization of the Progesterone and Oestrogen Receptors in the Magnum of the Immature Ostrich, Struthio camelus
Anatomia histologia embryologia, 2002Co-Authors: Mary-catherine MadekurozwaAbstract:Summary The immunolocalization of the progesterone (PR) and oestrogen receptors (OR), in the magnum of the immature ostrich, was investigated during periods of ovarian activity and inactivity. In the immature ostrich, with an active ovary, numerous well-developed Tubular Glands were present in the lamina propria. Significantly, PR immunostaining was strong in the surface epithelium and Tubular Glands of these birds. In contrast, weak staining for the PR was observed in the surface epithelium of birds with inactive ovaries. Tubular Gland formation, in these birds, was indicated by bud-like invaginations of the surface epithelium. Oestrogen receptor immunoreactivity was negligible in both birds with active and inactive ovaries. These findings suggest that steroid hormones, produced by the active ovary of the immature ostrich, influence the differentiation of the magnum. Furthermore, the action of these steroid hormones appears to be mediated through the PR.
S. Salomaa - One of the best experts on this subject based on the ideXlab platform.
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In situ hybridization of ovalbumin mRNA in the chick oviduct reveals target cell specificity for estrogen and progesterone.
The Journal of Steroid Biochemistry and Molecular Biology, 1992Co-Authors: S. Salomaa, T. Joensuu, Timo Ylikomi, Markku S. Kulomaa, T. Sannisto, P. TuohmaaAbstract:Abstract An in situ hybridization method using paraffin-embedded sections was used to characterize the chicken oviduct cells synthesizing ovalbumin mRNA due to the action of estrogen and progesterne. The cytodifferentiation of the oviduct cells was induced by 17β-estradiol administration to newly hatched female chicks. To avoid possible effect of estrogen on the action of progesterone the chicks were withdrawn from the estrogen by six days withdrawal period without hormone treatment. Ovalbumin mRNA was not synthesized after a period of estrogen withdrawal. Administration of estrogen induced ovalbumin mRNA in the Tubular Gland cells. Administration of progesterone induced the expression of ovalbumin mRNA in the surface epithelial cells. It was also found that progesterone induced mucus producing goblet cells in the surface epithelium. Estrogen did not have an effect on the mucus production, which suggests that progesterone could induce the terminal differentiation of the goblet cells. We conclude that the expression of ovalbumin in the surface epithelial cells and in the Tubular Gland cells is specific for progesterone and estrogen, respectively.
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Inducibility of the avidin gene by progesterone is suppressed during estrogen-induced cytodifferentiation
The Journal of steroid biochemistry and molecular biology, 1992Co-Authors: T. Joensuu, A. Niemelä, Tarja Kunnas, S. Salomaa, H. Alho, Pekka Vilja, Timo Ylikomi, Markku S. Kulomaa, Pentti TuohimaaAbstract:Abstract We have studied epithelial differentiation of the chick oviduct as induced by diethylstilbestrol (DES) and 17β-estradiol (E 2 ). The proportion of goblet cells in the oviduct was slightly higher after E 2 than after DES treatment. Also avidin induction by progesterone was stronger following DES than E 2 priming. In the estrogen pretreated oviduct epithelium, avidin expression was induced by progesterone in the surface epithelial cells, protodifferentiated Gland cells and Tubular Gland cells, but not in goblet cells. During prolonged estrogen treatment, however, the inducibility of avidin by progesterone ceased in Tubular Gland cells but not in surface epithelial cells. The estrogen action on the expression of avidin could be explained by estrogen-induced terminal differentiation of the epithelial Gland cells or by a direct effect of estrogen on the progesterone action, for instance interaction of estrogen receptor and progesterone receptor in the regulation of transcription.
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In situ hybridization of ovalbumin mRNA in the chick oviduct reveals target cell specificity for estrogen and progesterone.
The Journal of steroid biochemistry and molecular biology, 1992Co-Authors: S. Salomaa, T. Joensuu, T. Sannisto, T Ylikomi, M Kulomaa, P TuohimaaAbstract:An in situ hybridization method using paraffin-embedded sections was used to characterize the chicken oviduct cells synthesizing ovalbumin mRNA due to the action of estrogen and progesterone. The cytodifferentiation of the oviduct cells was induced by 17 beta-estradiol administration to newly hatched female chicks. To avoid possible effect of estrogen on the action of progesterone the chicks were withdrawn from the estrogen by six days withdrawal period without hormone treatment. Ovalbumin mRNA was not synthesized after a period of estrogen withdrawal. Administration of estrogen induced ovalbumin mRNA in the Tubular Gland cells. Administration of progesterone induced the expression of ovalbumin mRNA in the surface epithelial cells. It was also found that progesterone induced mucus producing goblet cells in the surface epithelium. Estrogen did not have an effect on the mucus production, which suggests that progesterone could induce the terminal differentiation of the goblet cells. We conclude that the expression of ovalbumin in the surface epithelial cells and in the Tubular Gland cells is specific for progesterone and estrogen, respectively.
T. Joensuu - One of the best experts on this subject based on the ideXlab platform.
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In situ hybridization of ovalbumin mRNA in the chick oviduct reveals target cell specificity for estrogen and progesterone.
The Journal of Steroid Biochemistry and Molecular Biology, 1992Co-Authors: S. Salomaa, T. Joensuu, Timo Ylikomi, Markku S. Kulomaa, T. Sannisto, P. TuohmaaAbstract:Abstract An in situ hybridization method using paraffin-embedded sections was used to characterize the chicken oviduct cells synthesizing ovalbumin mRNA due to the action of estrogen and progesterne. The cytodifferentiation of the oviduct cells was induced by 17β-estradiol administration to newly hatched female chicks. To avoid possible effect of estrogen on the action of progesterone the chicks were withdrawn from the estrogen by six days withdrawal period without hormone treatment. Ovalbumin mRNA was not synthesized after a period of estrogen withdrawal. Administration of estrogen induced ovalbumin mRNA in the Tubular Gland cells. Administration of progesterone induced the expression of ovalbumin mRNA in the surface epithelial cells. It was also found that progesterone induced mucus producing goblet cells in the surface epithelium. Estrogen did not have an effect on the mucus production, which suggests that progesterone could induce the terminal differentiation of the goblet cells. We conclude that the expression of ovalbumin in the surface epithelial cells and in the Tubular Gland cells is specific for progesterone and estrogen, respectively.
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Inducibility of the avidin gene by progesterone is suppressed during estrogen-induced cytodifferentiation
The Journal of steroid biochemistry and molecular biology, 1992Co-Authors: T. Joensuu, A. Niemelä, Tarja Kunnas, S. Salomaa, H. Alho, Pekka Vilja, Timo Ylikomi, Markku S. Kulomaa, Pentti TuohimaaAbstract:Abstract We have studied epithelial differentiation of the chick oviduct as induced by diethylstilbestrol (DES) and 17β-estradiol (E 2 ). The proportion of goblet cells in the oviduct was slightly higher after E 2 than after DES treatment. Also avidin induction by progesterone was stronger following DES than E 2 priming. In the estrogen pretreated oviduct epithelium, avidin expression was induced by progesterone in the surface epithelial cells, protodifferentiated Gland cells and Tubular Gland cells, but not in goblet cells. During prolonged estrogen treatment, however, the inducibility of avidin by progesterone ceased in Tubular Gland cells but not in surface epithelial cells. The estrogen action on the expression of avidin could be explained by estrogen-induced terminal differentiation of the epithelial Gland cells or by a direct effect of estrogen on the progesterone action, for instance interaction of estrogen receptor and progesterone receptor in the regulation of transcription.
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In situ hybridization of ovalbumin mRNA in the chick oviduct reveals target cell specificity for estrogen and progesterone.
The Journal of steroid biochemistry and molecular biology, 1992Co-Authors: S. Salomaa, T. Joensuu, T. Sannisto, T Ylikomi, M Kulomaa, P TuohimaaAbstract:An in situ hybridization method using paraffin-embedded sections was used to characterize the chicken oviduct cells synthesizing ovalbumin mRNA due to the action of estrogen and progesterone. The cytodifferentiation of the oviduct cells was induced by 17 beta-estradiol administration to newly hatched female chicks. To avoid possible effect of estrogen on the action of progesterone the chicks were withdrawn from the estrogen by six days withdrawal period without hormone treatment. Ovalbumin mRNA was not synthesized after a period of estrogen withdrawal. Administration of estrogen induced ovalbumin mRNA in the Tubular Gland cells. Administration of progesterone induced the expression of ovalbumin mRNA in the surface epithelial cells. It was also found that progesterone induced mucus producing goblet cells in the surface epithelium. Estrogen did not have an effect on the mucus production, which suggests that progesterone could induce the terminal differentiation of the goblet cells. We conclude that the expression of ovalbumin in the surface epithelial cells and in the Tubular Gland cells is specific for progesterone and estrogen, respectively.
Tatsudo Tamura - One of the best experts on this subject based on the ideXlab platform.
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involvement of apoptosis and lysosomal hydrolase activity in the oviducal regression during induced molting in chickens a cytochemical study for end labeling of fragmented dna and acid phosphatase
Poultry Science, 1997Co-Authors: B Heryanto, Tatsudo Tamura, Yukinori Yoshimura, T. OkamotoAbstract:Abstract Induced molting improves egg producing functions in hens. We investigated the mechanism of oviducal regression during induced molting. Involvement of apoptosis and autolysis in the oviducal regression process was analyzed by terminal deoxynucleotidyl transferase (T'dt)-mediated biotinylated deoxyuridine triphosphates (dUTP) nick end-labeling TUNEL) and an enzyme histochemistry for acid phosphatase. Nuclei positive for TUNEL were negligible and acid phosphatase staining was weak in the oviduct of laying hens. The frequency of TUNEL-positive nuclei was significantly increased in Tubular Gland cells of magnum, isthmus, and shell Gland 2 d after cessation of egg laying and significantly decreased thereafter. The intensity of acid phosphatase staining was gradually increased during oviducal regression and extremely high on Day 7 after cessation of egg laying. These results suggest that during oviducal regression in induced molting hens, apoptosis is induced in the earlier stage of oviducal regression and autolysis occurs thereafter eventually, the Glandular cells disappear.
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Immunocytochemical Localization of Vitamin D Receptors in the Shell Gland of Immature, Laying, and Molting Hens ☆
General and comparative endocrinology, 1997Co-Authors: Yukinori Yoshimura, Hiromi Ohira, Tatsudo TamuraAbstract:It is accepted that vitamin D is involved in the control of egg calcification in hens. The goal of this study was to localize the vitamin D receptors (VDR) in hen shell Gland and to determine whether their localization was dependent on reproductive function. Frozen sections of the shell Gland of immature, laying, and molting hens were immunostained for VDR, and the VDR in these tissues were also examined by Western blot analysis. Both apical and basal cells of the mucosal epithelium as well as Tubular Gland cells showed a strong immunoreaction for VDR in the shell Gland of laying hens. In the magnum and isthmus, the basal cells of the mucosal epithelium showed a moderately strong immunoreaction for VDR, whereas the immunoreactions in the apical cells of the mucosal epithelium and Tubular Gland cells were weak. In the shell Gland of immature birds, both the mucosal epithelium and Tubular Gland cells showed a moderately strong VDR immunoreaction. In molting hens, the mucosal epithelial cells and Tubular Gland cells showed a strong VDR immunoreaction although the mucosal tissue was regressed. Western blot analysis indicated that the mucosal tissue of the shell Gland of immature, laying, and molting hens contained two forms of immunoreactive VDR, which were approximately 58 and 60 kDa. Because VDR were richer in the shell Gland than in other oviductal segments, these results suggest that in laying hens the shell Gland tissues are one of the significant targets for vitamin D. It is likely that the amount of shell Gland VDR increases during sexual maturation and immunoreactive VDR remain even during the molting phase.
Michael B Thompson - One of the best experts on this subject based on the ideXlab platform.
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expression and localization of ca2 atpase in the uterus during the reproductive cycle of king quail coturnix chinensis and zebra finch poephila guttata
Comparative Biochemistry and Physiology A-molecular & Integrative Physiology, 2008Co-Authors: Scott L Parker, Laura A Lindsay, Jacquie F Herbert, Christopher R Murphy, Michael B ThompsonAbstract:Calcium ATPase (Ca2+-ATPase) is a key enzyme that participates in the translocation of calcium in the uterus of oviparous amniotes during eggshell formation. We used Western blot and indirect immunofluorescence microscopy to determine expression and localisation of uterine Ca2+-ATPase during the reproductive cycle of king quail and zebra finch. The pattern of Ca2+-ATPase expression and localisation during the reproductive cycle was similar for both species. Immunoblots of uterine extracts from quail and finch indicated that Ca2+-ATPase expression is reduced in non-reproductive compared to reproductive females. Similarly, in non-reproductive females, weak apical immunofluorescent staining of Ca2+-ATPase is localised to epithelial cells in a small number of uterine Tubular Glands. A large increase in apical immunofluorescent staining of Tubular Gland epithelia occurs in both vitellogenic and reproductive females. The presence of Ca2+-ATPase on the apical surface of Tubular Gland epithelial cells suggests that the enzyme is involved in the translocation of calcium out of the Tubular Gland epithelia and into the concentrated fluid of the uterine lumen. Presence of Ca2+-ATPase in vitellogenic females indicates that the enzyme is expressed prior to the time of ovulation and eggshell calcification.
