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Jan S Wojtaszek - One of the best experts on this subject based on the ideXlab platform.
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The effect of cortisol on the circulating blood parameters and on the activity of alanine and aspartate aminotransferases in the grass snake Natrix Natrix Natrix L.
Comparative Biochemistry and Physiology Part A: Physiology, 1993Co-Authors: Jan S WojtaszekAbstract:Abstract 1. 1. Sexually mature, laboratory-bred males Natrix n. Natrix were injected daily intraperitoneally with Cortisol (0.5 mg/100 g body wt of hydrocortisone acetate) in 0.9% saline, or saline only (control group). 2. 2. Three, 7 and 15 days after the first injection circulating blood parameters and alanine (A1AT) and aspartate (AsAT) activity in serum and in liver homogenates were measured. 3. 3. Lymphocytopenia, neutrophilic granulocytosis, eosinocytopenia and decrease in the white blood cell counts in circulating blood, but no significant changes in red blood cell system parameters were observed. 4. 4. The increased activity of A1AT and AsAT in the liver was not accompanied by significant changes in the level of those enzymes in the serum. 5. 5. The haematological changes observed and aminotransferase induction in the liver suggest that cortisol is a biologically active adrenal hormone, with an effect similar to that of corticosterone.
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Seasonal changes of circulating blood parameters in the grass snake Natrix Natrix Natrix L.
Comparative Biochemistry and Physiology Part A: Physiology, 1992Co-Authors: Jan S WojtaszekAbstract:Abstract 1. 1. Seasonal changes of circulating blood parameters of Natrix n. Natrix were evident and involved both sexes to the same extent. 2. 2. A significant decrease in red cell count, haematocrit and haemaglobin concentration in the mating period, and an increase in those parameters and mean cell volume in autumn were observed, and haemodilution during winter torpor. 3. 3. The changes during the breeding season had probably a hormonal background; in winter, they resulted first of all from a decreased erythropoietic activity and, to a lesser extent, from an increased red blood cell breakdown rate. However, the possibility that some erythrocytes were withdrawn from the circulation cannot be excluded. 4. 4. Winter lymphocytopenia, eosinocytopenia and neutrophilic granulocytosis in females during egg laying were expressions of changes of leucocyte formula. 5. 5. Seasonal cyclicity was found only with respect to the white cell count in males and the eosinophile fraction in males and females. 6. 6. Probable reasons for, and mechanisms of the changes in blood composition are discussed.
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Haematology of the grass snake Matrix Natrix Natrix L.
Comparative biochemistry and physiology. A Comparative physiology, 1991Co-Authors: Jan S WojtaszekAbstract:1. 1. Haematological parameters and cytomorphological plcture of circulating blood of the grass snake Natrix Natrix Natrix L. were studied. Mean annual values of the haemoglobin concentration, haematocrit level, red cell counts, erythrocyte indices, erythrocyte sedimentation rate, thrombocyte and leucocyte counts, per cent composition of white blood cells and size of morphotic elements were determined for a population sample (n = 154) of the species, considering the sex of snakes. 2. 2. Parameters of red blood cell system (RCC, Hb, Hct) were statistically significantly higher in males, remaining indices showed no statistically significant differences. 3. 3. A strict positive correlation was found between RCC, Hb and Hct in the studied sample. 4. 4. Cytomorphology of blood is presented in microphotographs. 5. 5. In the discussion haematological data for the grass snake and other snakes are compared.
Luca Luiselli - One of the best experts on this subject based on the ideXlab platform.
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The prey spectrum of Natrix matrix (LINNAEUS, 1758) and Natrix tessellata (LAURENTI, 1768) in sympatric populations (Squamata: Serpentes: Colubridae) Das Beutespektrum von Natrix Natrix (LINNAEUS, 1758) und Natrix tessellata (LAURENTI, 1768) in sympa
1996Co-Authors: Ernesto Filippi, Massimo Capula, Luca Luiselli, Umberto AgrimiAbstract:The prey spectrum of the Grass Snake, Natrix Natrix (LINNAEUS, 1758), and Dice Snake, N. tessellata (LAURENTI, 1768) was studied in rich sympatric populations in the vicinity of a stream located in a hilly area of central Italy ('Rota', Tolfa mountains, about 150 m a.s.l., 42° 08' N, 12° 00' E). Both species were frequently present in the water of the stream or close to it. Grass Snakes were also found far from the stream, and preyed on a variety of small vertebrate species. Conversely, Dice Snakes were strictly bound to the water and its vicinity, and preyed almost exclusively on fish. Dice Snakes did not show significant ontogenetic changes in their dietary spectrum other than that larger individuals tended to feed on larger prey. Conversely, in the Grass Snakes, there was a remarkable ontogenetic change in diet composition, and larger females tended to prey frequently upon adult toads (Bufo bufo), while adult males frequently fed upon 'green frogs'. The toads were usually preyed at a distance far from the water (average distance from the closest water body of a snake found with a toad in its stomach: 256.7 ±115.03 m, median: 233 m). About 91% of these toads were males. It is suggested that male toads were preyed more frequently than female toads because of their smaller size.
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Individual success in mating balls of the grass snake, Natrix Natrix: size is important
Journal of Zoology, 1996Co-Authors: Luca LuiselliAbstract:Natricine colubrid snakes, including the grass snake, Natrix Natrix, are frequently involved in complex social behaviour during the reproductive season. During these social behaviours, several males may simultaneously court a single female, resulting in a ‘ball’of mating snakes in which each male ‘combats’with rival males by ‘tail wrestling’(see Madsen & Shine, 1993). I performed some experiments in outdoor enclosures for testing the male-male competition and the determinants of mating success in male grass snakes involved in such ‘ball’aggregations. I demonstrated that competition between males occurred both when a single female was available to multiple males and when two females were simultaneously available to males. The larger males achieved more copulations than the smaller ones, thus demonstrating that body size is a crucial determinant of the individual mating success. It was not clear which aspect of male body size is the most important in determining success in these mating ‘balls’, but it was evident that the age of the ‘fighting’male was not correlated with mating success. Larger females attracted more males than smaller ones, both in the field and in the enclosure. Furthermore, when the size difference between available females in the cage was high, only the largest female was courted and coupled.
W Rupik - One of the best experts on this subject based on the ideXlab platform.
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Early development of the adrenal glands in the grass snake Natrix Natrix L. (Lepidosauria, Serpentes).
Advances in anatomy embryology and cell biology, 2002Co-Authors: W RupikAbstract:The aim of the study was to investigate the development and differentiation of the adrenal glands in the grass snake (Natrix Natrix L.) during the early stages of ontogenesis, i.e., from egg-laying to hatching of the first specimens. The material used for the studies consisted of a collection of embryos of the grass snake. The Natrix eggs were incubated in the laboratory at a constant temperature of 30 degrees C and 100% relative humidity. Embryos were isolated in a regular sequence of time from egg-laying to hatching. The age of the embryos was qualified according to normal tables for this species. For histological and histochemical investigations, the smallest embryos were fixed in toto. From the oldest embryos, the medial region with the mesonephros and adrenal primordium were resected. Depending on the requirements of histochemical methods, the material was fixed in various fixatives, namely, 10% formalin solution, Bouin, Wood and Millonig fluid, embedded in paraffin and sectioned into serial transversal, sagittal and longitudinal sections. The sections for review were stained with H&E and azan. For detection of adrenaline and noradrenaline in chromaffin tissue, the Wood and Honoré methods were used. SGC cells were detected with the silver stain method after Bodian. For electron microscopic studies, the adrenal gland was fixed in 2.5% glutaraldehyde and 2.0% paraformaldehyde 1:1 in 0.1 M phosphate buffer at pH 7.4 and post-fixed in 1.5% osmic acid in the same buffer. The fixed sections of the adrenal glands were embedded in Epon 812. Semithin and ultrathin sections were cut on ultramicrotome ultratome IV. Semithin sections were stained with methylene blue and ultrathin sections were routinely contrasted with uranyl acetate and lead citrate, then examined and photographed with the JEM JEOL 1220 electron microscope. According to morphological and metrical observation in the course of the grass snake embryo development, one can distinguish 12 stages of development. The primordia of the adrenal cortex appear at the first trimester of egg incubation as two asymmetrical strands between the mesonephros and aorta dorsalis. They are made of dense mesenchymal cells. At the second trimester of development, primordia are penetrated by chromaffinoblasts and capillaries. The mesenchymal cells differentiate into interrenal cells, while chromaffinoblasts are arranged dorsally of the gland. The glands are enclosed by the capsule which separates them from the mesonephros. At the third trimester of the eggs incubation, only noradrenaline appears in a chromaffin tissue. At the moment of snake hatching, the adrenal glands are completely differentiated, both in their structure and their function. The primordia of the interrenal tissue differentiate from mesenchymal cells similarly to mammals. During the development of the snake interrenal tissue, several types of cells can be recognized, varying in the degree of differentiation and in ultrastructural features: 1. Undifferentiated cells with features of mesenchymal cells 2. Differentiating mesenchymal cells 3. Transitional cells with features of mesenchymal and steroidogenic cells 4. Differentiating interrenal cells with pleomorphic mitochondria and numerous lipid droplets 5. Embryonic interrenal cells containing circular lipid droplets and underdeveloped smooth endoplasmic reticulum 6. Transitional interrenal cells containing mitochondria with tubular and vesicular cristae, large lipid droplets, numerous myelin structures, and well-developed smooth endoplasmic reticulum 7. Degenerating cells of embryonic interrenal tissue 8. Differentiating mesenchymal cells with features of fibroblasts The above classification is very schematic and presumptive. In developing adrenal glands at the first trimester of egg incubation type 1 and 2 cells predominate. Type 3 and 4 cells were observed at the second trimester of the adrenal primordia development. At the third trimester of egg incubation, embryonic adrenal glands were composed of the type 5 cells. At the moment of snake hatching, interrenal tissue contained type 5 and 6 cells. In the next days of the adrenal gland development, at the border between the cortex and in medulla as under the capsule, numerous cells were degenerated. During the entire development period the adrenal capsule was built from type 7 cells. The chromaffin tissue of the adrenal glands is derived from the neural crest. These findings agree with the findings of all embryologists. The first chromaffinoblasts infiltrated the adrenal cortex primordium around stage IV of development. They were mixed with interrenal cells and just at hatching they were localized dorsally of the gland. The chromaffinoblasts differentiated gradually from neuron-like cells to typical chromaffinocytes. All the chromaffinoblasts contained the chromaffin granules. The size and numerical density of the chromaffin granules increased with development. Just before hatching, the cells of the chromaffin tissue contained only noradrenaline. Differentiation chromaffinoblasts into chromaffin cells are probably stimulated and controlled by the influence of hormones, which are produced by the cells of the interrenal tissue. According to morphological, histochemical and ultrastructural observation in the course of adrenal differentiation and development in the grass snake, six morphological phases can be distinguished.
Weronika Rupik - One of the best experts on this subject based on the ideXlab platform.
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Development of pancreatic acini in embryos of the grass snake Natrix Natrix (Lepidosauria, Serpentes)
Journal of morphology, 2019Co-Authors: Magdalena Kowalska, Weronika RupikAbstract:This study report about the differentiation of pancreatic acinar tissue in grass snake, Natrix Natrix, embryos using light microscopy, transmission electron microscopy, and immuno-gold labeling. Differentiation of acinar cells in the embryonic pancreas of the grass snake is similar to that of other amniotes. Pancreatic acini occurred for the first time at Stage VIII, which is the midpoint of embryonic development. Two pattern of acinar cell differentiation were observed. The first involved formation of zymogen granules followed by cell migration from ducts. In the second, one zymogen granule was formed at the end of acinar cell differentiation. During embryonic development in the pancreatic acini of N. Natrix, five types of zymogen granules were established, which correlated with the degree of their maturation and condensation. Within differentiating acini of the studied species, three types of cells were present: acinar, centroacinar, and endocrine cells. The origin of acinar cells as well as centroacinar cells in the pancreas of the studied species was the pancreatic ducts, which is similar as in other vertebrates. In the differentiating pancreatic acini of N. Natrix, intermediate cells were not present. It may be related to the lack of transdifferentiation activity of acinar cells in the studied species. Amylase activity of exocrine pancreas was detected only at the end of embryonic development, which may be related to animal feeding after hatching from external sources that are rich in carbohydrates and presence of digestive enzymes in the egg yolk. Mitotic division of acinar cells was the main mechanism of expansion of acinar tissue during pancreas differentiation in the grass snake embryos.
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Development of endocrine pancreatic islets in embryos of the grass snake Natrix Natrix (Lepidosauria, Serpentes).
Journal of morphology, 2018Co-Authors: Magdalena Kowalska, Weronika RupikAbstract:Differentiation of the pancreatic islets in grass snake Natrix Natrix embryos, was analyzed using light, transmission electron microscopy, and immuno-gold labeling. The study focuses on the origin of islets, mode of islet formation, and cell arrangement within islets. Two waves of pancreatic islet formation in grass snake embryos were described. The first wave begins just after egg laying when precursors of endocrine cells located within large cell agglomerates in the dorsal pancreatic bud differentiate. The large cell agglomerates were divided by mesenchymal cells thus forming the first islets. This mode of islet formation is described as fission. During the second wave of pancreatic islet formation which is related to the formation of the duct mantle, we observed four phases of islet formation: (a) differentiation of individual endocrine cells from the progenitor layer of duct walls (budding) and their incomplete delamination; (b) formation of two types of small groups of endocrine cells (A/D and B) in the wall of pancreatic ducts; (c) joining groups of cells emerging from neighboring ducts (fusion) and rearrangement of cells within islets; (d) differentiated pancreatic islets with characteristic arrangement of endocrine cells. Mature pancreatic islets of the grass snake contained mainly A endocrine cells. Single B and D or PP-cells were present at the periphery of the islets. This arrangement of endocrine cells within pancreatic islets of the grass snake differs from that reported from most others vertebrate species. Endocrine cells in the pancreas of grass snake embryos were also present in the walls of intralobular and intercalated ducts. At hatching, some endocrine cells were in contact with the lumen of the pancreatic ducts.
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Does the grass snake (Natrix Natrix) (Squamata: Serpentes: Natricinae) fit the amniotes-specific model of myogenesis?
Protoplasma, 2017Co-Authors: Damian Lewandowski, Weronika Rupik, Magda Dubińska-magiera, Ewelina Posyniak, Małgorzata DaczewskaAbstract:In the grass snake ( Natrix Natrix ), the newly developed somites form vesicles that are located on both sides of the neural tube. The walls of the vesicles are composed of tightly connected epithelial cells surrounding the cavity (the somitocoel). Also, in the newly formed somites, the Pax3 protein can be observed in the somite wall cells. Subsequently, the somite splits into three compartments: the sclerotome, dermomyotome (with the dorsomedial [DM] and the ventrolateral [VL] lips) and the myotome. At this stage, the Pax3 protein is detected in both the DM and VL lips of the dermomyotome and in the mononucleated cells of the myotome, whereas the Pax7 protein is observed in the medial part of the dermomyotome and in some of the mononucleated cells of the myotome. The mononucleated cells then become elongated and form myotubes. As myogenesis proceeds, the myotome is filled with multinucleated myotubes accompanied by mononucleated, Pax7-positive cells (satellite cells) that are involved in muscle growth. The Pax3-positive progenitor muscle cells are no longer observed. Moreover, we have observed unique features in the differentiation of the muscles in these snakes. Specifically, our studies have revealed the presence of two classes of muscles in the myotomes. The first class is characterised by fast muscle fibres, with myofibrils equally distributed throughout the sarcoplasm. In the second class, composed of slow muscle fibres, the sarcoplasm is filled with lipid droplets. We assume that their storage could play a crucial role during hibernation in the adult snakes. We suggest that the model of myotomal myogenesis in reptiles, birds and mammals shows the same morphological and molecular character. We therefore believe that the grass snake, in spite of the unique features of its myogenesis, fits into the amniotes-specific model of trunk muscle development.
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Early Development of the Adrenal Glands in the Grass Snake Natrix Natrix L. (Lepidosauria, Serpentes)
2002Co-Authors: Weronika RupikAbstract:The aim of the study was to investigate the development and differentiation of the adrenal glands in the grass snake (Natrix Natrix L.) during the early stages of ontogenesis, i.e., from egg-laying to hatching of the first specimens. The material used for the studies consisted of a collection of embryos of the grass snake. The Natrix eggs were incubated in the laboratory at a constant temperature of 30 degrees C and 100% relative humidity. Embryos were isolated in a regular sequence of time from egg-laying to hatching. The age of the embryos was qualified according to normal tables for this species. For histological and histochemical investigations, the smallest embryos were fixed in toto. From the oldest embryos, the medial region with the mesonephros and adrenal primordium were resected. Depending on the requirements of histochemical methods, the material was fixed in various fixatives, namely, 10% formalin solution, Bouin, Wood and Millonig fluid, embedded in paraffin and sectioned into serial transversal, sagittal and longitudinal sections. The sections for review were stained with H&E and azan. For detection of adrenaline and noradrenaline in chromaffin tissue, the Wood and Honore methods were used. SGC cells were detected with the silver stain method after Bodian. For electron microscopic studies, the adrenal gland was fixed in 2.5% glutaraldehyde and 2.0% paraformaldehyde 1:1 in 0.1 M phosphate buffer at pH 7.4 and post-fixed in 1.5% osmic acid in the same buffer. The fixed sections of the adrenal glands were embedded in Epon 812. Semithin and ultrathin sections were cut on ultramicrotome ultratome IV. Semithin sections were stained with methylene blue and ultrathin sections were routinely contrasted with uranyl acetate and lead citrate, then examined and photographed with the JEM JEOL 1220 electron microscope. According to morphological and metrical observation in the course of the grass snake embryo development, one can distinguish 12 stages of development. The primordia of the adrenal cortex appear at the first trimester of egg incubation as two asymmetrical strands between the mesonephros and aorta dorsalis. They are made of dense mesenchymal cells. At the second trimester of development, primordia are penetrated by chromaffinoblasts and capillaries. The mesenchymal cells differentiate into interrenal cells, while chromaffinoblasts are arranged dorsally of the gland. The glands are enclosed by the capsule which separates them from the mesonephros. At the third trimester of the eggs incubation, only noradrenaline appears in a chromaffin tissue. At the moment of snake hatching, the adrenal glands are completely differentiated, both in their structure and their function. The primordia of the interrenal tissue differentiate from mesenchymal cells similarly to mammals. During the development of the snake interrenal tissue, several types of cells can be recognized, varying in the degree of differentiation and in ultrastructural features: 1. Undifferentiated cells with features of mesenchymal cells 2. Differentiating mesenchymal cells 3. Transitional cells with features of mesenchymal and steroidogenic cells 4. Differentiating interrenal cells with pleomorphic mitochondria and numerous lipid droplets 5. Embryonic interrenal cells containing circular lipid droplets and underdeveloped smooth endoplasmic reticulum 6. Transitional interrenal cells containing mitochondria with tubular and vesicular cristae, large lipid droplets, numerous myelin structures, and well-developed smooth endoplasmic reticulum 7. Degenerating cells of embryonic interrenal tissue 8. Differentiating mesenchymal cells with features of fibroblasts The above classification is very schematic and presumptive. In developing adrenal glands at the first trimester of egg incubation type 1 and 2 cells predominate. Type 3 and 4 cells were observed at the second trimester of the adrenal primordia development. At the third trimester of egg incubation, embryonic adrenal glands were composed of the type 5 cells. At the moment of snake hatching, interrenal tissue contained type 5 and 6 cells. In the next days of the adrenal gland development, at the border between the cortex and in medulla as under the capsule, numerous cells were degenerated. During the entire development period the adrenal capsule was built from type 7 cells. The chromaffin tissue of the adrenal glands is derived from the neural crest. These findings agree with the findings of all embryologists. The first chromaffinoblasts infiltrated the adrenal cortex primordium around stage IV of development. They were mixed with interrenal cells and just at hatching they were localized dorsally of the gland. The chromaffinoblasts differentiated gradually from neuron-like cells to typical chromaffinocytes. All the chromaffinoblasts contained the chromaffin granules. The size and numerical density of the chromaffin granules increased with development. Just before hatching, the cells of the chromaffin tissue contained only noradrenaline. Differentiation chromaffinoblasts into chromaffin cells are probably stimulated and controlled by the influence of hormones, which are produced by the cells of the interrenal tissue. According to morphological, histochemical and ultrastructural observation in the course of adrenal differentiation and development in the grass snake, six morphological phases can be distinguished.
Małgorzata Daczewska - One of the best experts on this subject based on the ideXlab platform.
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Does the grass snake (Natrix Natrix) (Squamata: Serpentes: Natricinae) fit the amniotes-specific model of myogenesis?
Protoplasma, 2017Co-Authors: Damian Lewandowski, Weronika Rupik, Magda Dubińska-magiera, Ewelina Posyniak, Małgorzata DaczewskaAbstract:In the grass snake ( Natrix Natrix ), the newly developed somites form vesicles that are located on both sides of the neural tube. The walls of the vesicles are composed of tightly connected epithelial cells surrounding the cavity (the somitocoel). Also, in the newly formed somites, the Pax3 protein can be observed in the somite wall cells. Subsequently, the somite splits into three compartments: the sclerotome, dermomyotome (with the dorsomedial [DM] and the ventrolateral [VL] lips) and the myotome. At this stage, the Pax3 protein is detected in both the DM and VL lips of the dermomyotome and in the mononucleated cells of the myotome, whereas the Pax7 protein is observed in the medial part of the dermomyotome and in some of the mononucleated cells of the myotome. The mononucleated cells then become elongated and form myotubes. As myogenesis proceeds, the myotome is filled with multinucleated myotubes accompanied by mononucleated, Pax7-positive cells (satellite cells) that are involved in muscle growth. The Pax3-positive progenitor muscle cells are no longer observed. Moreover, we have observed unique features in the differentiation of the muscles in these snakes. Specifically, our studies have revealed the presence of two classes of muscles in the myotomes. The first class is characterised by fast muscle fibres, with myofibrils equally distributed throughout the sarcoplasm. In the second class, composed of slow muscle fibres, the sarcoplasm is filled with lipid droplets. We assume that their storage could play a crucial role during hibernation in the adult snakes. We suggest that the model of myotomal myogenesis in reptiles, birds and mammals shows the same morphological and molecular character. We therefore believe that the grass snake, in spite of the unique features of its myogenesis, fits into the amniotes-specific model of trunk muscle development.
