[Distribution of glycoconjugates terminal sugars during neurohypophysis development in rat]

The neurohypophysis originates from the floor of diencephalon. Its development controles by several cellular interactions that mediated by some molecules such as cell surface and extra cellular matrix Glycoconjugates terminal sugars. In this study we used lectin histochemichal technique to evaluate distribution of the Glycoconjugates and their changes during development of neurohypophysis. This experimental study carried on 40 female and 20 male adult Rats. After mating and appointment day zero of pregnancy, pregnant Rats were sacrificed from days 10-20 of gestation and their embryos were collected for histochemical study. The serial section of head specimens were fixed and incubated with different HRP-lectins from Orange fungus [OFA] Vicica villosa [VVA], Glycine max [SBA], Wistaria floribunda [WFA], peanut [PNA], Griffonia simplicfolia [GSA1-B4], Lotus tetragonolobus [LTA] and Ulex Europeus [UEA-1]. OFA, LTA and UEA-1 lectins are specific for terminal sugars alpha -L-Fucose and WFA, SBA, VVA and PNA are specific for D-GalNAc, alpha, beta -D-GalNAc and GalNAc, D-Gal-[beta -1-3]- DGalNAc of complex glycoconjugates respectively. Our findings demonstrated that the reaction of neurohypophysis cells with OFA initiated from gestational GD10 and increased to GD15 [P<0.05] and then increased to GD17 [P<0.05]. A few cells of neurohypophysis reacted with PNA from GD13 to GD16 and decreased afterward [P<0.05]. Some cells of neurohypophysis reacted with SBA from GD14 to GD18 and decreased afterward [P<0.05]. Reacting of many cells of neurohypophysis with WFA started on GD13 and increased to GD15 [P<0.05] and then decreased afterward [P<0.05]. Neurohypophysis cells showed no reaction with the UEA-1, LTA, VVA and GSA1-B4 lectins. The expression of Glycoconjugates with terminal sugars alpha -L-Fucose, alpha, beta -D-GalNAc and D- Gal- [beta -1-3]- D-GalNAc have importanct role and special spatiotemporal situation in neurohypophysis development

[Assessment of glycoconjugates terminal sugars expression during rat skin morphogenesis]

This study was conducted in order to determine distributions and changes of glycoconjugates terminal sugars during skin morphogenesis. Using lectin histochemistry technique, 10% formalin fixed, paraffin embedded rat embryonic sections for days 12, 14, 16 of gestation [1SN30] were incubated with different HRP-lectins from Lotus tetragonolobus [LTA], Maclura pomifera[MPA] and Arachis hypogaea or Peanut [PNA] that are specific for terminal alpha-L Fuc, Gal[beta1->3] GalANC and D-Gal[beta1->3]DGalNAC respectively. On the basis of colonmetery data that was determined by blind's method, sections were graded. SPSS statistic soft ware and Kruskal-Wallis non-parametric statistical test were used to compare different embryonic stages. Our results demonstrated that the reaction of ectodermal cells with LTA observed from gestational day 12 [E12] was weak. This reaction increased E14 significantly [p=0.0001] and then decreased. Extracellular matrix [ECM] of mesenchyme did not react with LTA lectin. Ectodermal cells as well as ECM of mesenchyme reacted with PNA on El2 was fairly weak. It increased E14 [p=0.009]. From E14 to E16 intensity staining remain the same in ectodermal cells but decreased in ECM mesenchyme [p=0.0001]. Ectodermal cells and ECM of mesenchyme reacted with the MPA lectins from E12 to E16. According to our result, it is suggested that the distributions and changes of glycoconjugates with terminal sugars L-Fuc [alpha2-4] GlcNAC, Gal [[beta 1->3] GalNAC and D-Gal [brta1->3] DGalNAC be stage - regulated during rat skin morphogenesis

[Maternal nexposure on collagen type IV pulmonary changes in mouse offspring's]

In this study we evaluated the effect of maternal nicotine administration during pre and postnatal period on collagen IV changes in lung of mouse newborns. Female Balb/C mice were mated and finding vaginal plug was assumed as day zero of pregnancy. Pregnant mice, were divided into 2 experimental and 2 control groups. Experimental group 1, received 3 mg/kg nicotine intrapritoneally from day 5 of gestation to last day of pregnancy. Experimental group 2 received the same amount of nicotine during the same gestational days as well as the first two week after birth [lactation]. The control groups received the same volume of normal saline during the same periods. At the end of exposure time, all of newborns [experimental and control] were anesthetized and their lungs were removed and immunohistochemical study for tracing collagen were carried out. Our finding indicated that collagen reaction in the bronchial basement membrane [BBM] and extra cellular matrix [ECM] of lung parenchyma in experimental increased significantly in comparison to control groups. Cell necrosis definition in lung parenchyma of experimental group 2 were the other finding that our investigation achieved. These data indicate that maternal nicotine exposure may induce a noticeable increasing collagen reasonable in BBM and ECM of respiratory system of next generation. The lungs of these animals which were exposed to nicotine via the placenta and mother's milk, are more susceptible to damages such as abnormal collagen synthesis and cell necrosis

[ key role of type IV collagen in developing retinal basement membrane in mouse]

Basement membranes are specialized extracellular matrices serve as development, proliferation and substrates for migration. Collagen fibers specially type IV, are the most important part of this area. As retina is one of the target organs in diabetes mellitus and diabetic retinopathy and diabetic nephropathy are major cause of end stage - renal and retinal diseases and resulting in increased in morbidity and mortality of effected individuals, therefore early diagnosis leads to better treatment. Investigation the appearance and distribution of collagen IV during gestational days and early postnatal period. 24 intact female Balb/c mice were kept under normal nutrition and environment condition. After mating, vaginal plug was assumed as zero day of pregnancy. From [13[th]-18[th]] days, gestation pregnant mice were sacrified and their embryos as well as pups from 1st to 5th days were collected. For histochemichal studies, the head of specimens were fixed, histological preparation was done and by using monocolonal antibody against for tracing of collagen type IV were carried out. Our finding revealed that amount of collagen IV in internal limiting membrane [ILM] and extra cellular matrix [ECM] of the retina appearance on embryonic 16[th] day and increase continuously until end stage of embryonic life. In addition, strong labeling was observed until 3rd day of postnatal period but these reactions did not increase significantly after these periods. These findings indicate that retinal development is dependent on different proteins by special regards specially collagen IV

[ effect of formaldehyde on somniferous tubules of Balb/c mice]

To examine the effect of formaldehyde on somniferous ducts of laboratory animals. This study investigated 24 male Balb/c mice 20 days old that randomly divided into experimental and control groups. The Experimental group was administered every other days at the rate of 0.25 mg/kg formaldehyde intrapritoneally for 20 days. The control group received the same volume of normal saline during the same period of times. At the end of exposure time, the sample of both groups were anesthetized and Transected. Their removed testies were processed, serially sectioned and histochemically studied. Our findings showed that the mean of internal diameter of somniferous tubules decreased significantly in experimental group compared to control group while the mean of external diameter was the same in both groups. Furthermore the prolifration rates of I and II spermatocytes were decreased significantly in experimental group compared to control group. The findings indicate that administration of formldehyde can influence the structure of male reproductive system and affect on spermatogenesis procedure

[Study of expression type IV collagen during mouse kidney ubulogenesis in Balb/c mouse]

In this study specific antibody have been used for tracing type IV collagen basement membrane during renal tubules morphogenesis in mouse fetuses. 20 female Balb/C mice were selected randomly and were kept under normal condition, finding vaginal plug was assumed as day zero of pregnancy. 12 pregnant mice were sacrified by cervical dislocation in one of gestational days 13-18 and their fetuses were fixed, serially sectioned and immunohistochemistry study for tracing of collagen type IV in BMG was carried out. The same processes were used for kidneys preparation on 5, 10, 15 and 20 postnatal days newborns of 2 mothers for each day. Based on our data, Collagen IV showed weak reaction on day 14 of gestation in tubular BM. The amount of collagen increased continuously until next days of fetal life and primary of 5 days postnatal in BM. After this period, collagen IV reaction was not showed significant change in newborns. These results indicate that developmental changes in various nephron segments from most immature stages to most differentiated structures are dependent to the type IV collagen expression

effect of camphor on seminiferous tubules of Balb/c mice

Background and Purpose:_In Iranian traditional medicine, it has been widely believed that camphor is a suppressor of sexual desire. Based on this idea and the few studies about this issue, we examined the effect of camphor on the histological changes and spermatogenesis phenomena in the mouse reproductive system

Materials and Methods: In this experimental study, 24 premature male balb/c mice were selected and divided into four [2 experimental and 2 control] groups. Experimental groups 1 and 2 were administered daily 30 mg/kg body weight dissolved camphor in olive oil [orally] for 10 and 20 days respectively. The control groups received the same volume of olive oil during the same periods. At the end of the exposure time, each group was anesthetized and their testes were routinely removed for obtaining serial sections and histological staining. The obtained data were analyzed using t-test

Results: The study data indicated that although the mean external diameter of the somniferous tubules did not show significant differences in experimental and control groups, the mean internal diameter tubules [26/31 +/- 1/56] of the experimental groups [versus control groups 42/38 +/- 2/19] decreased by %25, and mature sexual cells [17/ +/- 3/71] in the experimental groups [versus control groups 28 +/- 3/92] decreased by %12

Conclusion: The results of the present study indicated that administration of camphor significantly decreased the internal diameter of Somniferous tubules and reduced maturity of sexual cells; hence, affecting the reproductive system of the male mice with structural changes

Study of the histological changes of mouse intervertebral disc development

At least two different elements can be detected in the structure of mature intervertebral disc. The central portion contains nucleus pulpous. Its few cells being embedded in gel form material. The outer protein, however, is called annulus fibroses, composed of concentric layers of intertwined annulus bands. Although the major anatomical structures of intervertebral disc are well known, there are little information on the development of its components such as cell type and extracellular matrix. Therefore, this study was conducted to study the histological changes in the development of intervertebral disc in mouse. In this study, collagen fiber appearance and cellular differentiation were studied using serial section and histological staining methods in the course of intervertebral disc development in mouse embryo. The findings indicated that from the 12th day of gestation, the notochord starts getting separated from the floor plate of neural tube. Gradually on the next days, as mesenchyme cells get condensed around, patterns of intervertebral disc differentiation can be observed, leading to disc development toward the end of gestation. Throughout this process, the notochord degenerates. Theses changes start from the middle portion of notochord and proceeds towards head and tail. Then vertebral bodies are forward in portions with degenerated notochord changes. During the development changes of intervertebral disc, remnants of notochord form nucleus pulpous in the intervertebral disc. However, the mesenchyme surrounding it [forthcoming annulus fibrosus] consist of structurally dissimilar regions, Under these circumstances, the outer portion is made up of highly-densed collagen material but in the inner portion, remnants of embryonic hyaline cartilage and collagen fibers can be detected

effect of camphor on the male mice reproductive system

In Iranian traditional medicine there is a belief that camphor is a suppressor of sexual activity. Based on this idea and since there are few studies on this issue, we evaluated the effect of camphor on histopathological changes of reproductive system in young male mice of balb/c racial type. Thirty-six premature male balb/c mice, were divided into 3 paired groups of experimental, control, and sham [n=6]. Experimental groups 1 and 2 received 30 mg/kg camphor dissolved in olive oil [orally] for 10 and 20 days, respectively. The control groups received the same volume of olive oil during the same periods of time, and no intervention was done in sham groups. All groups were kept in the same environmental condition. At the end of exposure time, each group was anesthetized and their testes were removed for obtaining serial sections, and histological staining. Comparing to the control groups less vascularization in testis tissue of experimental groups was seen. Furthermore, using stereological methods demonstrated that internal diameters of seminiferous tubules in experimental groups were significantly smaller than those in control groups [P<0.005]. Also, the number of released sexual cells was lower in experimental groups [P<0.005]. No meaningful difference was seen between controls and sham groups. Administration of camphor and its effects on male mice reproductive system may result in significant structural changes, including vascularization and proliferation of sexual cells. This can affect maturation of seminiferous tubules and subsequently, reproductive function of testes in mice

[ role of glycoconjugates in development of floor plate during early morphogenesis in mouse embryo]

The floor plate is a small group of cells located at the ventral midline of neural tube. During early neurogenesis, the floor plate plays critical role [s] in differentiation of ventral portion of neural tube. The purpose of this study was to determine the distribution of glycoconjugates in floor plate as well as underlying mesoderm [notochord] and their inductive activities in mouse embryos. Formalin fixed sections embedded in paraffin from 10 to 14 days old Balb/C mouse embryos were processed for histochemical studies by using five deferent horseradish peroxidase [HRP] labelled lectins including; Glycin max [SBA] specific for Gal and GalNac terminal sugar, Vicia Villosa [VVA] and Arachis hypogaea peanut] for GalNac, Ulex europeus [UEA-I] and Lotus tetragonolobus [LTA] for a- L-fucose. Our results showed that SBA sensitive glycoconjugates react and change in floor plate, notochordal cells and surrounding extracellular matrix and these changes were significant [P<0.05]. Extensive differences between GalNac sensitive lectins were observed during motoneuron differentiation. There was no reaction with other tested GalNac lectins. Furthermore we observed significant changes [P<0.05] in fucose glycoconjugates during notochordal development. The results suggest that the timing and distribution of SBA sensitive glycoconjugates may play a key role [s] in interactions and subsequent formation of adjacent tissues such as floor plate and notochord during critical period of morphogenesis. Our finding also showed that glycoconjugates with fucose terminal sugar might play a role [s] in notochordal development but probably have no function on floor plate development

Developmental changes of glycoconjugates in early mouse embryonic neuroepithlium, notochordal and surrounding mesenchymal interactions

During early neural tube formation, the notochord is essentialfor the induction of ectoderm and for the subsequent differentiation of theneuroepithelium forming diverse cell types in the neural tube. Due to thekey role of the glycoconjugates in many developmental events, the earlydistribution of these molecules in early notochordal interaction withadjacent tissues were studied. Material and Paraffin fixed 5m sections of days 10 to 14 of mouse embryo were processed for histochemical studies by using horseradish peroxidase labelled DBA, VVA-B4, WFA, UEA-1 and OFA lectins.These lectins have binding specificity for D-GalNac and a-fucose sidechains of the glycoconjugates. Histochemical analysis revealed that notochord and itsintermediate extracellular fluid show extensive reaction with the floor plateof neural tube on 10th day, using OFA. This reaction was absent in thenext day but a sever reaction was observed in the floor plate region. Theresults revealed a reaction in venteral portion of notochord with VVA-B4and it expanded in to gut tube. Furthermore, a WFA-reaction was observedin the notochord and some of adjacent mesenchymal cells, but UEA-1 and DBA, don't showed any reaction. The expression of the GalNac and also fucosilatedglycoconjugates is stage-dependent and thus probably geneticallyregulated. The timing and distribution of lectin reactions suggest that thesemolecules [GalNac and fucose] may play a role[s] in notochordalinteractions and subsequent formation of the adjacent tissues

Estrogen - induced congenital hypospadias in developing rat embryos

Hypospadius is a defect of the urethra and penis in the male. In this research the incidence of the male hypospadius induced by estrogen [estradiol] administration was investigated during embryonic development. Three groups of pregnant rats were exposed to 0.15mg/kg estradiol valerate via a single intramuscular injection on one of the following gestational days: 12, 14 or 16 and named as experimental groups 1,2 and 3 respectively. All the pregnant rats were sacrificed on the last day of pregnancy [day 20]. The fetuses collected and counted and the external genitalas examined for detection of hypospadius as well as other malformations. The data showed that in addition to the significant reduction in the size of the litters in experimental groups, the incidence of the male hypospadius is high, especially in the group 1. Furthermore, most of the fetuses had severe malformations including anencephaly, exencephaly, agnatha, syndactyly and tetradactyly