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Types of cells present in the anterior pituitary gland and its classification
Microanatomy of the pars distalis showing chromophobes, basophils and acidophils
The pars distalis, (distal part), comprises the majority of the anterior pituitary and is where the bulk of pituitary hormone production occurs. The pars distalis contains two types of cells including chromophobe cells and chromophil cells.[1] The chromophils can be further divided into acidophils (alpha cells) and basophils (beta cells).[1] These cells all together produce hormones of the anterior pituitary, and release them into the blood stream.
Corticotrophs Basophil,Thyrotrophs Basophil,Gonadotrophs Basophil,Somatotrophs Acidophil andLactotrophs Acidophil
التاريخ
25/12/2016 16:50:28
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أماني قاسم حسن GroupA2
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A major organ of the endocrine system, the anterior pituitary (also called the adenohypophysis or pars anterior), is the glandular, anterior lobe that together with the posterior lobe (posterior pituitary, or the neurohypophysis) makes up the pituitary gland (hypophysis). The anterior pituitary regulates several physiological processes including stress, growth, reproduction and lactation. Proper functioning of the anterior pituitary and of the organs it regulates can often be ascertained via blood tests that measure hormone levels.Anterior pituitary cells first were classified by their staining behaviour in light microscopic preparations. Later they were classified according to the type of hormone they produce. Although even electron microscopy has been routinized, the functional classification of anterior pituitary cells was not easy. Experimental morphology that was mainly based on observation of the anterior pituitary after extirpation of target endocrine organs was the only method for identifying the probable function of each cell type in the anterior pituitary. The use of antibody against each hormone, that is immunohisto(cyto-)chemistry at light and electron microscopic level, was an epoch-making innovation in the technique for studying endocrine morphology. The technique revealed two or three morphologically different types in each cell group containing the same hormone. These subtypes in cell classification by immuno-electron microscopy are related to the age and sex of the animal. Cell biological research using electron microscopy, especially immunocytochemistry, clarified mechanisms concerning various steps in hormone production, for example, the synthesis of peptide hormones (precursors) in the rough endoplasmic reticulum; transfer to the Golgi apparatus; modification and processing of precursor peptides during the passage through Golgi stacks and the trans-Golgi network that corresponds to GERL; the moving of secretory granules; the mechanism of exocytosis and related membrane events; and the activity of lysosomes related to such endocrine functions as crinophagy and the recycling of membrane constituents retrieved from the cell surface after exocytosis of secretory granules.
التاريخ
25/12/2016 16:49:39
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رقيه ميثم حسين A2
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Give a brief report about the types of cells present in the anterior pituitary gland..and how they are classified
You should be able to see two types of chromophils (cells which take up stain) called acidophils and basophils.
Acidophils and basophils are divided into different classes of cells which have different secretory products and target organs.
The anterior pituitary contains five types of endocrine cell, and they are classified by the hormones they secrete: somatotropes (GH); prolactins (PRL); gonadotropes (LH and FSH); corticotropes (ACTH) and thyrotropes (TSH
These cannot be distinguished by H&E or other histological stains, but can be stained specifically by immunohistochemical techniques.
The capillaries in this gland are fenestrated, to enable passage of hormones from the secretory cells into the bloodstream.
التاريخ
25/12/2016 16:17:45
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تبارك تحسين ضياء A1
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In the anterior pituitary, the term "acidophil" is used to describe two different types of cells:
somatotrophs, which generate somatotropin (also known as growth hormone)
mammotrophs, which generate prolactin
An anterior pituitary basophil is a type of cell in the anterior pituitary which manufactures hormones.
It is called a basophil because it is basophilic (readily takes up bases), and typically stains a relatively deep blue or purple.
Cell name Relative proportion Hormone produced Hypothalamic regulators
Corticotrophs 15% ACTH CRH
Gonadotrophs 10% FSH, LH and hCG* GnRH
Thyrotrophs 5% TSH TRH
التاريخ
25/12/2016 15:16:54
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هالة اياد حسن Group B2
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الكروب A1
anterior pituitary is made up of a number of cell types that are essential for such physiological processes as growth, development, homeostasis, metabolism, and reproduction. These include the hormonal cells corticotropes, thyrotropes, gonadotropes, somatotropes, lactotropes and a small population of mammosomatotropes, together with a non-hormonal cell type called the folliculo-stellate cells. The anterior pituitary hormonal cells are highly differentiated and are committed very early on during embryonic development. Their development is tightly regulated by both extrinsic signals as well as by endogenous gene expression. Many transcription factors that shape the development and functions of the anterior pituitary cells have been identified. Even after differentiation, pituitary cells continue to undergo mitosis and this process could be augmented under certain conditions in adulthood. Some anterior pituitary cells are multifunctional and exhibit mixed phenotypes. Pituitary tumors, which are mostly monoclonal in nature, are rather common. The molecular pathogenesis of pituitary tumorigenesis involves complex and diverse mechanisms. Aberrant intra- and extra-pituitary factors are involved. Mutations of some genes specific to pituitary tumors also play a role.
. Thecells
oftheanteriorpituitary,whicharenamedaccording
tothetrophichormonesthattheyproduce,includethe
following celltypes:corticotropes(adrenocorticotropic
hormone(ACTH)andrelatedpeptidesproducing
cells),thyrotropes(thyroidstimulatinghormone(TSH)
producingcells),gonadotropes(luteinizinghormone
(LH)and folliclestimulating hormone(FSH) producing
cells),somatotropes(growthhormone(GH)producing
cells),andlactotropes(prolactin(PRL)producing
cells).Asmallpopulationofmammosomatotropes
alsoexistswhichproducesbothGHandPRL.These
hormonal cellsareassociated with anon-hormonal cell
type in theanteriorpituitary calledthefolliculo-stellate
التاريخ
25/12/2016 14:55:02
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مريم كاظم
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In the anterior pituitary, the term "acidophil" is used to describe two different types of cells:
somatotrophs, which generate somatotropin (also known as growth hormone)
mammotrophs, which generate prolactin Fatima hussien:
An anterior pituitary basophil is a type of cell in the anterior pituitary which manufactures hormones.
It is called a basophil because it is basophilic (readily takes up bases), and typically stains a relatively deep blue or purple.
Cell name Relative proportion Hormone produced Hypothalamic regulators
Corticotrophs 15% ACTH CRH
Gonadotrophs 10% FSH, LH and hCG* GnRH
Thyrotrophs 5% TSH TRH
التاريخ
25/12/2016 14:53:53
كتب السؤال
هالة اياد حسن Group B2
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الكروب /A1
anterior pituitary is made up of a number of cell types that are essential for such physiological processes as growth, development, homeostasis, metabolism, and reproduction. These include the hormonal cells corticotropes, thyrotropes, gonadotropes, somatotropes, lactotropes and a small population of mammosomatotropes, together with a non-hormonal cell type called the folliculo-stellate cells. The anterior pituitary hormonal cells are highly differentiated and are committed very early on during embryonic development. Their development is tightly regulated by both extrinsic signals as well as by endogenous gene expression. Many transcription factors that shape the development and functions of the anterior pituitary cells have been identified. Even after differentiation, pituitary cells continue to undergo mitosis and this process could be augmented under certain conditions in adulthood. Some anterior pituitary cells are multifunctional and exhibit mixed phenotypes. Pituitary tumors, which are mostly monoclonal in nature, are rather common. The molecular pathogenesis of pituitary tumorigenesis involves complex and diverse mechanisms. Aberrant intra- and extra-pituitary factors are involved. Mutations of some genes specific to pituitary tumors also play a role.
. Thecells
oftheanteriorpituitary,whicharenamedaccording
tothetrophichormonesthattheyproduce,includethe
following celltypes:corticotropes(adrenocorticotropic
hormone(ACTH)andrelatedpeptidesproducing
cells),thyrotropes(thyroidstimulatinghormone(TSH)
producingcells),gonadotropes(luteinizinghormone
(LH)and folliclestimulating hormone(FSH) producing
cells),somatotropes(growthhormone(GH)producing
cells),andlactotropes(prolactin(PRL)producing
cells).Asmallpopulationofmammosomatotropes
alsoexistswhichproducesbothGHandPRL.These
hormonal cellsareassociated with anon-hormonal cell
type in theanteriorpituitary calledthefolliculo-stellate
التاريخ
25/12/2016 14:53:40
كتب السؤال
براء محمد سعيد
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Q4/list the type of the cell in the anterior pituitary gland ?
Anterior pituitary cells
The anterior pituitary is made up of a number of cell types that are essential for such physiological processes as growth, development, homeostasis, metabolism and reproduction.it s contains five types of endocrine cell, and they are defined by the hormones they secrete: somatotropes (GH); prolactins (PRL); gonadotropes (LH and FSH); corticotropes (ACTH) and thyrotropes (TSH). Other classification according to the affinity of the colorant used in histochemistry (acid or basic colorant).it s two type acidophil and basophil.
The term "acidophil" is used to describe two different types of cells:
* somatotropes (growth hormone ( GH ) producing cells)
* lactotropes (prolactin (PRL) producing cells).
The term "basophil" is used include the following cell types:
* corticotropes (adrenocorticotropic hormone (ACTH) and related peptides producing cells)
* thyrotropes (thyroid stimulating hormone (TSH) producing cells)
* gonadotropes (luteinizing hormone (LH) and follicle stimulating hormone (FSH) producing cells).
The acid-basic characteristic of the pituitary cells is due to the hormone they contain in granules. From the analysis of the aminoacidic sequence is possible to calculate the protein aminoacids percentage (graph 1, graph 2) and the isoelectric point of the proteins(graph3):
التاريخ
25/12/2016 11:44:19
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هالة هادي مكي b2
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