Template:Endocrine embryo table: Difference between revisions
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* [[Endocrine - Thyroid Development|Thyroid]] - median thyroid is now bilobed and is connected to the pharynx by a hollow pedicle.<ref name=Weller1933>{{Ref-Weller1933}}</ref> The telopharyngeal body has been regarded as a "lateral thyroid component" by some workers.<ref name=Weller1933>{{Ref-Weller1933}}</ref> | * [[Endocrine - Thyroid Development|Thyroid]] - median thyroid is now bilobed and is connected to the pharynx by a hollow pedicle.<ref name=Weller1933>{{Ref-Weller1933}}</ref> The telopharyngeal body has been regarded as a "lateral thyroid component" by some workers.<ref name=Weller1933>{{Ref-Weller1933}}</ref> | ||
* Pancreas - ventral pancreas may perhaps be distinguishable (Politzer 1952). | * Pancreas - ventral pancreas may perhaps be distinguishable (Politzer 1952). | ||
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| [[Carnegie stage 14|'''Stage 14''']] (week 5) | | [[Carnegie stage 14|'''Stage 14''']] (week 5) | ||
* [[Endocrine - Pituitary Development|Hypophysis]] - craniopharyngeal pouch is prominent (Streeter 1945) and the notochord appears to be inserted into its dorsal wall. The craniopharyngeal pouch has become elongated and blood vessels are beginning to grow in between the basement membranes of the pouch and brain (O'Rahilly 1973a). | * [[Endocrine - Pituitary Development|Hypophysis]] - craniopharyngeal pouch is prominent (Streeter 1945) and the notochord appears to be inserted into its dorsal wall. The craniopharyngeal pouch has become elongated and blood vessels are beginning to grow in between the basement membranes of the pouch and brain (O'Rahilly 1973a). | ||
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* Adrenal Cortex - primordium is first recognizable. A new type of cell (C1) from the coelomic epithelium is found in the subjacent mesenchyme. New cells (C2) appear in the medial wall of mesonephric glomeruli and begin to migrate into the suprarenal primordium.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> Jirfisek (1980) denies a mesonephric contribution to the suprarenal. | * Adrenal Cortex - primordium is first recognizable. A new type of cell (C1) from the coelomic epithelium is found in the subjacent mesenchyme. New cells (C2) appear in the medial wall of mesonephric glomeruli and begin to migrate into the suprarenal primordium.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> Jirfisek (1980) denies a mesonephric contribution to the suprarenal. | ||
* Adrenal Medulla - all types of cells (M1, M2, and M3) increase in number. From stage 15 to stage 18, the suprarenal primordium is cigar-shaped and extends from segment T6 to segment L1, lateral to the aorta and mesogastrium.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | * Adrenal Medulla - all types of cells (M1, M2, and M3) increase in number. From stage 15 to stage 18, the suprarenal primordium is cigar-shaped and extends from segment T6 to segment L1, lateral to the aorta and mesogastrium.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | ||
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| [[Carnegie stage 16|'''Stage 16''']] (week 6) | | [[Carnegie stage 16|'''Stage 16''']] (week 6) | ||
* [[Endocrine - Pituitary Development|Hypophysis]] - slight indication of the infundibular recess may be seen in some embryos (O'Rahilly 1973 a). | * [[Endocrine - Pituitary Development|Hypophysis]] - slight indication of the infundibular recess may be seen in some embryos (O'Rahilly 1973 a). | ||
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* Adrenal Medulla - first neural migration is at its height. Growth of the para-aortic complex is extensive. The plexiform complex is derived from paravertebral sympathetic ganglia T6-12 and usually L 1. Included in it are the primordia of the suprarenal medulla and of the celiac, superior mesenteric, and renal plexuses. Nerve fibres and "paraganglion" (M3) cells enter. | * Adrenal Medulla - first neural migration is at its height. Growth of the para-aortic complex is extensive. The plexiform complex is derived from paravertebral sympathetic ganglia T6-12 and usually L 1. Included in it are the primordia of the suprarenal medulla and of the celiac, superior mesenteric, and renal plexuses. Nerve fibres and "paraganglion" (M3) cells enter. | ||
* Pancreas - ventral pancreas has now fused with dorsal (Streeter 1948). Perhaps the ventral and dorsal ducts have begun to blend (Russu and Vaida 1959). | * Pancreas - ventral pancreas has now fused with dorsal (Streeter 1948). Perhaps the ventral and dorsal ducts have begun to blend (Russu and Vaida 1959). | ||
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| [[Carnegie stage 18|'''Stage 18''']] (week 7) | | [[Carnegie stage 18|'''Stage 18''']] (week 7) | ||
* [[Endocrine - Pineal Development|Epiphysis]] - cellular migration in the pineal body forms a distinct "anterior lobe" in which follicles appear (Stadium 3 of Turkewitsch 1933) (O'Rahilly 1973 a). | * [[Endocrine - Pineal Development|Epiphysis]] - cellular migration in the pineal body forms a distinct "anterior lobe" in which follicles appear (Stadium 3 of Turkewitsch 1933) (O'Rahilly 1973 a). | ||
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* Adrenal Cortex - C2 cells lie on the surface of the gland and form a "capsule".<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | * Adrenal Cortex - C2 cells lie on the surface of the gland and form a "capsule".<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | ||
* Adrenal Medulla - Sympathicoblasts penetrate the cortex at stages 19 and 20, and form scattered islets of medullary tissue throughout the cortex (Jirfisek 1980). | * Adrenal Medulla - Sympathicoblasts penetrate the cortex at stages 19 and 20, and form scattered islets of medullary tissue throughout the cortex (Jirfisek 1980). | ||
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| [[Carnegie stage 20|'''Stage 20''']] | | [[Carnegie stage 20|'''Stage 20''']] | ||
* [[Endocrine - Pituitary Development|Hypophysis]] - the adenohypophysial epithelium adjacent to the neurohy- pophysis constitutes the beginning pars intermedia (O'Rahilly 1973 a). The walls of the craniopharyngeal pouch bud into the mesenchyme (Andersen et al. 1971 ; Jirfisek 1980). | * [[Endocrine - Pituitary Development|Hypophysis]] - the adenohypophysial epithelium adjacent to the neurohy- pophysis constitutes the beginning pars intermedia (O'Rahilly 1973 a). The walls of the craniopharyngeal pouch bud into the mesenchyme (Andersen et al. 1971 ; Jirfisek 1980). | ||
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* [[Endocrine - Pituitary Development|Hypophysis]] - the pharyngeal stalk becomes fragmented (Jirfisek 1980). | * [[Endocrine - Pituitary Development|Hypophysis]] - the pharyngeal stalk becomes fragmented (Jirfisek 1980). | ||
* Adrenal Cortex - the cellular "capsule" becomes covered by a layer of fibrous tissue.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | * Adrenal Cortex - the cellular "capsule" becomes covered by a layer of fibrous tissue.<ref name=Crowder1957>{{Ref-Crowder1957}}</ref> | ||
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| [[Carnegie stage 22|'''Stage 22''']] | | [[Carnegie stage 22|'''Stage 22''']] | ||
* [[Endocrine - Parathyroid Development|Parathyroids]] - Parathyroids 4 become detached from the pharyngeal endoderm (Jirfisek 1980). | * [[Endocrine - Parathyroid Development|Parathyroids]] - Parathyroids 4 become detached from the pharyngeal endoderm (Jirfisek 1980). |
Revision as of 13:39, 1 November 2016
Human Embryonic Endocrine |
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Pineal (Epiphysis) | Pituitary (Hypophysis) | Thyroid | Parathyroid | Thymus | Pancreas | Adrenal (Suprarenal)
Data based on data from O'Rahilly (1983).[1] |
Stage 13 (week 4)
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Stage 14 (week 5)
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Stage 15
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Stage 16 (week 6)
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Stage 17
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Stage 18 (week 7)
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Stage 19
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Stage 20
(1938), of migration of and covering by "cells derived from the cervical sinus".
Weller (1933, Fig. 23) showed parathyroid 3 still rostral to parathyroid 4 at 23 mm, whereas (presumably due to variation in the "descent" of the thymus) Norris (1937, Fig. 4) showed parathyroid 3 rostral to, level with, and caudal to parathyroid 4 in embryos of 16-17 mm. |
Stage 21
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Stage 22
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Stage 23
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References
<reference/> |
- ↑ O'Rahilly R. The timing and sequence of events in the development of the human endocrine system during the embryonic period proper. (1983) Anat. Embryol., 166: 439-451. PMID 6869855
- ↑ 2.00 2.01 2.02 2.03 2.04 2.05 2.06 2.07 2.08 2.09 2.10 2.11 Weller GL. Development of the thyroid, parathyroid and thymus glands in man. (1933) Contrib. Embryol., Carnegie Inst. Wash. 24: 93-139.
- ↑ 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 Crowder RE. The development of the adrenal gland in man, with special reference to origin and ultimate location of cell types and evidence in favor of the "cell migration" theory. (1957) Contrib. Embryol., Carnegie Inst. Wash. 36, 193-210.
- ↑ Odgers PN. Some observations on the development of the ventral pancreas in man. (1930) J. Anat., 65(1): 1-7. PMID 17104298
- ↑ Blechschmidt E. Die prdnatalen Organsysteme des Menschen. (1973) Hippokrates, Stuttgart.
- ↑ O'Rahilly R. The development of the epiphysis cerebri and the subcommissural complex in staged human embryos. (1968) Anat. Rec., 160: 488-489.