RESUMEN
In a previous work we demonstrated the relationship between nerve fibers and nerve endings and interstitial cells (estrogen-producing cells) from the atrophic right ovary and the medulla in the left functioning ovary during embryogenesis in the chick, in ovo. Besides, the local production of neurotrophins by steroidogenic cells is probably involved in the control of ovarian innervation. The objective of the present study was to analyze ultrastructurally the innervation during the differentiation of chick ovary cultured with 17-beta-estradiol. Explants of right and left ovaries from seven to nineteen days in ovo development were cultured separately for 4 days in MEM (controls) or in the presence of 17-beta-estradiol (problems). In controls the electron microscopic examination of the innervation explants from chick embryo ovaries revealed that the interstitial cells are well innervated. Nerve fibres and nerve endings were observed in close contact with steroid-producing cells, a similar pattern of innervation that those of the fifteen days ovaries in ovo development. Problems cultured from seven days showed nerve fibres and nerve endings at difference to controls. These results in vitro suggest that innervation of the ovaries is controlled by indirect mechanism via the hypothalamic-pituitary system and local production factors. More experiments are necessary to confirm this results.
RESUMEN
The purpose of the present work was to analyze the structural variations produced [quot ]in vitro[quot ] by hormones on the cell surfaces of the ovarian epithelium of the chick embryo, in relation to the growth of the left ovary and atrophy of the right one. Explants of both ovaries from embryos at 7 to 19 days of development were separately cultured for 4 days in MEM with 10
of fetal bovine serum (control), and plus 17-beta-estradiol, testosterone propionate, progesterone, FSH, LH or hCG added individually to cultures (experimental). The cultures were processed for their structural, ultrastructural and cytochemical study. In control cultures, membrane differentiations and mucosubstances were similar in both ovaries and at all ages to those in ovo. 17-beta-estradiol produced a greater development of microvilli, junctional complexes and mucin in the epithelial cells and interdigitations in the germ cells of the left ovary, while in the right gonad there was cell regression. Testosterone and progesterone evoked in the left gonad a response similar to that obtained with the estrogen, whereas in the right ovary no changes were observed with respect to controls. FSH led to cellular regression in both ovaries. Finally, with LH or hCG the changes produced in the left ovary were similar to those induced by the estrogen, and in the right one an increase of membrane differentiations and of mucosubstances related to them was found in comparison to controls.(ABSTRACT TRUNCATED AT 250 WORDS)
RESUMEN
Variations of the intercellular junctions of the germ and epithelial cells of the ovarian epithelium produced by gonadotropic and esteroid hormones were determined on ovaries of the chick embryo at 7 days of development. Explants of right and left ovaries were cultured without (control) or with hormones eddition (experimental) for 4 days. Cultures were processed for their ultrastructural study. In both control ovaries the union complexes were similar to those identified in ovo. Under the action of 17 beta-estradiol, an increase and a greater development of adherens junctions was observed in the left ovary; in the right ovary, adherens junctions diminished by action of 17 beta-estradiol. The response of the left ovary to progesterone and testosterone was similar to that seen with the estrogen. No changes were observed in the right gonad. A disminution of intercellular junctions was produced in both ovaries under the action of FSH. The changes produced by LH and hCG were similar to those find in the left ovary with the estrogen, consisting of an increase of the union complexes, mainly of the adherens type. These results indicate that steroid and gonadotropic hormones act by modifying intercellular junctions and would participate in the processes of growth and atrophy that occur in the ovaries of the chick embryo.
RESUMEN
Having studied the functioning left ovary and the atrophic right ovary of the chicken during its in ovo embryogeny, we decided to study its development in vitro. For that purpose the explants of left and right ovaries of 7 at 19 days of in ovo development were cultured in Eagle medium, supplemented by bovine fetal serum and lated processed for structural and ultrastructural studies. At every ages the left ovary showed a cortex and a medulla while the right ovary had no cortex. Epithelial cells were observed in the cortex, encircling ovocytes having typical Balbianis bodies formed by mitochondria, Golgi aparatus and centriole. Some nuclei were in the meiotic prophase. The right ovary and the medulla of the left ovary failed to show the lacunar aspect characteristic in the ovo study. Conversely, cell cords were found, formed by epithelial cells and ovocytes which being very close to each other, gave the cord a compact aspect. Among the cords, groups of interstitial cells could be seen, which were more frequent in the cultures of older ova and in both ovaries. The left and the right ovaries, therefore, developed according to the genetic pattern. Notwithstanding, the left ovary medulla and the right ovary would be modulated by extragonadal factors which would be inactive when the gonads are not in their natural environment.
RESUMEN
The ovary of the chick embryo starts differentiation from the 7th day of development. The left ovary grows progressively, whereas the right one undergoes involution. With the purpose of determining the degree of regression of the right ovary in relation to the diverse types of granular cells that form it, an ultrastructural study was made of embryonic ovaries of 7, 11, 15 and 19 days old. Three types of granular cells are described: A cells, similar to granulocytes, with phagocytic functions, B cells with semi-dense granules and functionally active C cells with granules of low electronic density. During development, A cells remain in the right ovary until 19 days. Nevertheless, there is not an increase in their amount in the involuting ovary. B cells diminish in the right ovary from 7 to 19 days; however, no modifications are found in the left ovary. These cells are considered precursors of the C cells due to the transition forms found in both cell types. C cells are seen in similar proportions in both ovaries at all the embryonic stages studied. It is important to note that there is a difference in the mechanism of hormonal induction at the level of these cells in the ovary that progresses as compared to the one that undergoes atrophy. Precursor B cells would be destroyed in the right ovary before undergoing a complete functional differentiation. These observations would indicate that both B and C cells are involved in the hormonal control of differentiation and estrogen secretion in both ovaries. With respect to type A cells, further studies are needed to establish their function.
RESUMEN
It has been established that differentiation of the female gonad of the chicken is different in the right and left ovaries. Whereas the left ovary differentiates into the adult functional ovary, the right one suffers regressive changes and does not participate in the production of ova. Hence, we considered of importance to study the structural, ultrastructural and cytochemical characteristics of interstitial cells, which secrete estrogens in the left ovary and in the right one that undergoes atrophy, which has not been yet analyzed in this aspect. Chick embryos at 7, 11, 15 and 19 days of incubation were employed. The techniques used were H/E, Sudan IV, 3 -beta- hydroxysteroid dehydrogenase and transmission electron microscopy. At the light microscope these cells were clearly identified in the medullary cords, grouped in nests circumscribed by connective tissue, since 11 days of incubation. With H/E they exhibited a cytoplasm of foamy aspect and clear vacuoles of variable size. The amount of cell nests increased with the ages of the embryos. Besides, we found accumulation of sudanophilic granules and an enzymatic activity that increased during the course of development. At the ultrastructural level these cells contained an abundant smooth endoplasmic reticulum with tubules and vesicles, mitochondrias with tubular cristae and a considerable number of lipidic inclusions. The above mentioned elements confer to these cells and steroid-secreting activity. It is noteworthy that in the ovary that regresses interstitial cells do not disappear. In conclusion, we may point out that the right ovary would be rudimentary in ova formation, but would remain active with respect to hormonal secretion.(ABSTRACT TRUNCATED AT 250 WORDS)
RESUMEN
The early lesions induced in the pancreas of dogs by the intraductal injection of bile-trypsin were studied. Histological, histochemical and electron microscopic techniques were used. The primary lesions analyzed thirty three minutes after the induction of pancreatitis consisted in cell alterations, blood stasis and oedema. At first, the affected acinar cells showed enlargement of the rough endoplasmic reticulum cisternae, later they were disrupted and then appeared vesicles with ribosomes adhering to the external surface. Mitochondria were swelled and showed cristae disrupted which finally appeared destroyed. The zymogen granules lost density, decreased in size and number and later disappeared, Ducts maintained the normal structure and their cells were still observed in areas where the tissue was greatly destroyed. the results obtained suggest that: 1) The experimental acute pancreatitis induced by bile-trypsin is characterized by primary and severe damage in the acinar cells, with secondary ischemia due to stasis and intravascular coagulation. 2) Cellular rests and probably endogenous enzymes invade the periacinar spaces, then would penetrate into the vascular system producing the generalization of lesions.
RESUMEN
The embryonic gonads produce and secrete the steroid hormones that induce secondary sex differentiation in different species. The production of estrogens, testosterone and progesterone by interstitial cells of the chick embryo ovary has been demonstrated in experiments in ovo and in vitro. Estrogens would be responsible at the 7th day of in ovo incubation, of the evolution of the functional left ovary. According to Gasc, only the cells of the germinative epithelium of the left ovary possess receptors for estrogens, thus originating the formation of a cortex in this functional gonad and not in the right one. On the other hand, extragonadal factors, such as gonadotrophins, would participate in gonadal differentiation. Involvement of the hypophysis in the morphological and functional differentiation of the ovary in the chick embryo, has been considered in several studies. Woods and Week established the functional hypophysealgonadal axis at 13 days of in ovo incubation. However, the effects of individual gonadotrophins on the interstitial cells of the chick embryo remain unclear. Avila et al. and Grassi Milano observed that when the female gonads were cultured without steroid or gonadotrophic hormones at the start of differentiation an hermaphrodite left ovary and a male right one were formed. Kyparissi and Vakolopoulu observed that the inoculation in ovo of FSH at the end of embryonic development led to an increment in the number and size of follicles in the left ovary. Pittini and Grassi Milano added FSH and LH to cultures of 15 days-old chick embryos testicles and ovaries and found that only male gonads developed similar to normal embryos.(ABSTRACT TRUNCATED AT 250 WORDS)
RESUMEN
In previous works we showed a probable relationship between plasma membrane and its differentiations in ovary epithelium with maturation of the left ovary in chick embryo. To elucidate this aspect a cytochemical and ultrastructural study of the germinal epithelium from 7 to 19 days-old chick embryos was performed. Cytochemical and ultracytochemical techniques for mucosubstances localization and transmission electron microscopy were used. At 7 days the epithelium of right and left ovary showed epithelial cells with microvilli and junctional complexes. Irregular folds and projections appeared in the germ cells. Both cell types possessed a coat with a light reaction in the right gonad and more intense in the left one when they were stained with Alcian blue, PAS or Ruthenium Red. From 11 to 19 days, in the left ovary epithelium the layers of cells were increased and presented discontinuous basement membranes and absence of cell projections. On the contrary, in basal and germ cells these structures were increased. The mucosubstances increased from the 15th day. At this time the right ovary showed a simple epithelium with cells without projections. The germ cells disappeared in this ovary and a marked decrement of mucosubstances was observed. These results indicate that it exists a direct relationship between cellular morphogenesis and the mucosubstances of membranes. These substances may play a special role in the cellular migration of the left ovary since they were not detected in the right gonad which suffers regression and embryonic atrophy.
RESUMEN
In a previous work we demonstrated that germ and epithelial cells of the atrophic right ovary and of the medulla in the left functioning ovary undergo regression while interstitial cells are preserved. The objective of the present study was to analyze the relationship between nerve fibers and nerve endings and interstitial cells from both ovaries during embryogenesis in the chick. To this purpose, left and right ovaries from embryos of 7 to 19 days of development were processed for ultrastructural study and ultracytochemical determination of acid phosphatase. At 7 days, isolated interstitial cells were found in the central region of both ovaries, containing SER, Golgi apparatus, mitochondria with tubular cristae and abundant lipidic vacuoles. Nerve fibers and nerve endings were scarce. From the 11th day, interstitial cells were found grouped in the right ovary and in the medulla of the left one, and were related to nerve bundles surrounded by Schwann cells. The nerve ending, in close contact with the membrane of interstitial cells, contained mitochondria, microtubules and small and big vesicles, some with an electro-dense content. This relationship between interstitial cells and nerve endings and fibers was more frequent from the 15th day. The activity of acid phosphatase localized in germ and epithelial cells presented a more intense reaction in the right ovary and in the medulla of the left ovary at 15 days.(ABSTRACT TRUNCATED AT 250 WORDS)
RESUMEN
The purpose of the present work was to analyze the structural variations produced [quot ]in vitro[quot ] by hormones on the cell surfaces of the ovarian epithelium of the chick embryo, in relation to the growth of the left ovary and atrophy of the right one. Explants of both ovaries from embryos at 7 to 19 days of development were separately cultured for 4 days in MEM with 10
of fetal bovine serum (control), and plus 17-beta-estradiol, testosterone propionate, progesterone, FSH, LH or hCG added individually to cultures (experimental). The cultures were processed for their structural, ultrastructural and cytochemical study. In control cultures, membrane differentiations and mucosubstances were similar in both ovaries and at all ages to those in ovo. 17-beta-estradiol produced a greater development of microvilli, junctional complexes and mucin in the epithelial cells and interdigitations in the germ cells of the left ovary, while in the right gonad there was cell regression. Testosterone and progesterone evoked in the left gonad a response similar to that obtained with the estrogen, whereas in the right ovary no changes were observed with respect to controls. FSH led to cellular regression in both ovaries. Finally, with LH or hCG the changes produced in the left ovary were similar to those induced by the estrogen, and in the right one an increase of membrane differentiations and of mucosubstances related to them was found in comparison to controls.(ABSTRACT TRUNCATED AT 250 WORDS)
RESUMEN
Ultrastructural descriptions in birds are scarce thus, in this study we have characterized the secretory granules of mucous and seromucous cells from the palatine and lingual salivary glands of birds with different diets. The samples were taken from the tongue and palatine mucosa of chicken (Gallus gallus), quail (Coturnix coturnix), chimango (Milvago chimango) and white heron (Egretta thula). The samples were processed for observation by transmission electron microscopy (TEM) employing 4
Karnovsky solution for fixation. The most noteworthy finding was the heterogeneous ultrastructural appearance of the secretory granules. Differences in substructure were found between the four species, between the palatine and lingual glands in the same species and even within the same acinus and the same cell. At variance with other authors, these differences cannot be attributed to the type of fixative solution used taking into account that all the samples were processed in the same way. Previous histochemical studies have shown the presence of sulfated and non sulfated glycoconjugates in these glands which can be associated to the maturation of the granules. These granules are probably representative of peculiar storage of the secretory products that would give rise to a heterogeneous and complex ultrastructural pattern of granules in the mucosa and seromucosa cells of these avian species.
RESUMEN
The morpho-histochemical alterations that occur in the chicken ovary at 7 days of incubation after irradiation with He-Ne laser of a potency of 5 mw and at a wavelength of 632.8 nm were studied. The embryos were irradiated for 5 minutes through a window opened in the eggshell and aseptically maintained in incubator for 24 hours. The gonads were dissected out and processed for the following techniques: H/E, PAS, alcian blue, and toluidine blue. Controls: The ovaries were formed by a germinative or superficial epithelium, with germ and epithelial cells, and by primary sex cords compressed between them, although separated by a reduced stroma. The cords contained germ cells The surface coat of the germinative epithelium presented a thin layer of PAS positive, alcianophilic at pH 25 and orthochromatic material. Basement membranes and intercord extracellular substance were also PAS positive. Problems: Disorganization of the tissue structure was well manifest in irradiated gonads, accompanied by negativization of the histochemical reactions. A lymphocytic infiltration was also found. No structural alterations were observed in germ or epithelial cells. It is concluded that laser radiations would act producing decrease of the mucosubstances associated to the plasma membrane and basement membrane. They would also provoke the appearance of an inflammatory mononuclear infiltration.
RESUMEN
Evolutionary, structural, ultrastructural and cytochemical studies (PAS, alcian blue, toluidine blue, Ruthenium red) were performed in chick tongues 7 to 19 days development, with the aim of observing the histomorphological changes during growth and differentiation. At 7 days the tongue was covered by a flat epithelium without cornification, with four cell lines. As an axis was observed a central hyaline-cartilaginous skeleton surrounded by mesenchyma. Since 11 days appeared glandular buds and canalized cell cords united trough complexes. At 15 days the epithelial thickness increased remarkably. The subepithelial connective tissue, already notably differentiated, formed papillae. Glandular acini contained PAS positive, alcianophilic, metachromatic and positive ruthenium red substance. Ultrastructurally, glands showed clear cells, with decreased electronic density and organoids randomly distributed and dark cells having electrodense cytoplasm and more organized organoids. At 19 days the epithelium was cornified in the tongue anterior half. A net increment of glycoconjugates was detected in glands. These observations show: 1) lingual glands secrete mucins since 15 days of embryonic development; 2) the cornified anterior epithelium is the result of a genetic pattern and not of a later functional adaptation to the type of feeding (grain eating birds).
RESUMEN
The structural and histochemical patterns of the salivary mesenchyma were analysed in relation to the epithelium of the labial glands during the embryonic development to correlate the structural and histochemical characteristics in both tissues during the histogenesis. Samples of human fetal lips were analysed using H/E, PAS, Cason, Alcian blue, Toluidine blue and Methenamine/silver. The process of glandular histogenesis begun between 8 to 10 weeks. The mesenchyma surrounding the glandular buds had PAS positive granulations which were also alcianophilic, metachromatic and periodatoreactive. Periodatoreactive collagenous fibrillae, reticular cells and nervous fibers of considerable diameter were observed. Basement membranes were PAS positive, alcianophilic and discontinuous. At 12 weeks the mesenchyma differentiated as loose connective tissue which produced a delicate periglandular capsule with fibroblast and collagenous fibrillae. From 20 to 24 weeks the acini were structurally and histochemically differentiated as serous, mucous and mixed. It was postulated that the periglandular mesenchyma would play and important role in the morphogenetic process in relation to the histochemical identification of molecules which have a specific biological functions in the epithelium-mesenchyma interactions during organogenesis.
RESUMEN
We have studied the thyroid tissue present in a cystic ovarian teratoma with the purpose of characterizing its structural and histochemical components. The methods of hematoxilyn and eosin, PAS, PAS/sialidase, Alcian blue at pH 2.5 and 1.0, were used, as well as, blocking reactions, Casons thrichromic, and toluidine blue at pH 3.8. In the tissue we observed zones with follicles of normal appearance that varied considerably in size. The epithelium was constituted by cuboid cells surrounding a colloid substance of uniform aspect, that was strongly acidophilic, PAS positive and with variable reactivity with toluidine blue and weakly alcianophilic. With the thrichrome method, the different follicles stained in different tones. Parafollicular clear cells, bigger and less basophilic than follicular ones, with a nucleus having a lax chromatin, were identified. Cystic follicles were observed in whose cavities were conspicuous histyocytes surrounding rests of colloid substance, with metachromatic and PAS positive granules in their cytoplasm. Some groups of follicles were rudimentary, scarcely differentiated, and mostly without colloid. Others, with a greater degree of differentiation, showed diminutes follicles with intensely basophilic and PAS positive colloid. Beasides, follicular groups with excessive content of colloid appeared very distended and lined by a flat epithelium. According to the characteristics analyzed it may be concluded that: 1) it is a highly differentiated monoblastic teratoma, in which it appears non-encapsulated thyroid tissue; 2) the tumor resembles in different areas, either normal thyroid tissue, thyroid adenoma of the macrofollicular type, fetal or microfollicular and solid or embryonary adenoma, and follicles with the pattern of [quot ]thyroiditis[quot ].
RESUMEN
The structural and histochemical patterns of the salivary mesenchyma were analysed in relation to the epithelium of the labial glands during the embryonic development to correlate the structural and histochemical characteristics in both tissues during the histogenesis. Samples of human fetal lips were analysed using H/E, PAS, Cason, Alcian blue, Toluidine blue and Methenamine/silver. The process of glandular histogenesis begun between 8 to 10 weeks. The mesenchyma surrounding the glandular buds had PAS positive granulations which were also alcianophilic, metachromatic and periodatoreactive. Periodatoreactive collagenous fibrillae, reticular cells and nervous fibers of considerable diameter were observed. Basement membranes were PAS positive, alcianophilic and discontinuous. At 12 weeks the mesenchyma differentiated as loose connective tissue which produced a delicate periglandular capsule with fibroblast and collagenous fibrillae. From 20 to 24 weeks the acini were structurally and histochemically differentiated as serous, mucous and mixed. It was postulated that the periglandular mesenchyma would play and important role in the morphogenetic process in relation to the histochemical identification of molecules which have a specific biological functions in the epithelium-mesenchyma interactions during organogenesis.
RESUMEN
Evolutionary, structural, ultrastructural and cytochemical studies (PAS, alcian blue, toluidine blue, Ruthenium red) were performed in chick tongues 7 to 19 days development, with the aim of observing the histomorphological changes during growth and differentiation. At 7 days the tongue was covered by a flat epithelium without cornification, with four cell lines. As an axis was observed a central hyaline-cartilaginous skeleton surrounded by mesenchyma. Since 11 days appeared glandular buds and canalized cell cords united trough complexes. At 15 days the epithelial thickness increased remarkably. The subepithelial connective tissue, already notably differentiated, formed papillae. Glandular acini contained PAS positive, alcianophilic, metachromatic and positive ruthenium red substance. Ultrastructurally, glands showed clear cells, with decreased electronic density and organoids randomly distributed and dark cells having electrodense cytoplasm and more organized organoids. At 19 days the epithelium was cornified in the tongue anterior half. A net increment of glycoconjugates was detected in glands. These observations show: 1) lingual glands secrete mucins since 15 days of embryonic development; 2) the cornified anterior epithelium is the result of a genetic pattern and not of a later functional adaptation to the type of feeding (grain eating birds).
RESUMEN
Human von Ebners glands were analyzed during fetal and childhood development, and adultness, with the purpose of observing possible age-related cytochemical changes. Tongues from 8-38 weeks-old fetuses, samples of the lingual V from newborns, 8 to 14 years-old children and adults aged 20 years and older were used. H/E, and techniques for mucosubstances (PAS, PAS/amylase, PAS/sialidase, methenamine-silver, Alcian blue at pH 2.5 and 1.0, and Toluidine blue at pH 3.8) were employed. Between 16 and 20 weeks acini and ducts in the process of formation were identified, being the parenchyma completely developed at 24 weeks. The morphology of glands from newborns consisted of basophilic and periodate-negative serous acini. In infants secretory cells contained PAS positive apical granules that were sensitive to sialidase, periodate-reactive and slightly metachromatic. These characteristics were increased with age. Besides, in adults, the apical cytoplasm of the adenomerous and the luminal content were also alcianophilic. The cytochemical variations observed indicates that human von. Ebners glands are composed of cells of the seromucous type that contain sialomucins and sulphomucins.
RESUMEN
The morpho-histochemical alterations that occur in the chicken ovary at 7 days of incubation after irradiation with He-Ne laser of a potency of 5 mw and at a wavelength of 632.8 nm were studied. The embryos were irradiated for 5 minutes through a window opened in the eggshell and aseptically maintained in incubator for 24 hours. The gonads were dissected out and processed for the following techniques: H/E, PAS, alcian blue, and toluidine blue. Controls: The ovaries were formed by a germinative or superficial epithelium, with germ and epithelial cells, and by primary sex cords compressed between them, although separated by a reduced stroma. The cords contained germ cells The surface coat of the germinative epithelium presented a thin layer of PAS positive, alcianophilic at pH 25 and orthochromatic material. Basement membranes and intercord extracellular substance were also PAS positive. Problems: Disorganization of the tissue structure was well manifest in irradiated gonads, accompanied by negativization of the histochemical reactions. A lymphocytic infiltration was also found. No structural alterations were observed in germ or epithelial cells. It is concluded that laser radiations would act producing decrease of the mucosubstances associated to the plasma membrane and basement membrane. They would also provoke the appearance of an inflammatory mononuclear infiltration.