Anatomy (endo) Flashcards
What is the function of the hypothalamus and how does it achieve this?
Function= control of homeostasis
Integrates signals from internal organs and makes adjustments to internal environment (e.g. autonomic response, temp regulation, food/water intake) and endocrine control)
What are the boundaries of the hypothalamus?
its boundaries= (1) the anterior commissure and lamina terminalis anteriorly; (2) mammillary bodies and midbrain posteriorly, and (3) thalamus superiorly
What is the anterior commissure?
Extension of corpus callosum
What is the diamond shape seen below?
Floor of hypothalamus
What are mammilary bodies?
The mammillary bodies are brainstem nuclei on the posteroinferior aspect of the hypothalamus
What are mammilary bodies?
ADD FLASHCARD
The mammillary bodies are brainstem nuclei on the posteroinferior aspect of the hypothalamus
What is the thalamus made of?
Collection of nuclei (cell bodies within the nervous system)
What are two important nuclei in the hypothalamus connected to the endocrine system?
Paraventricular nucleus, has projections of axons into the posterior pituitary
Supraoptic nucleus also has projections
Both release oxytocin and vasopressin (ADH) into the blood stream at pituitary
What is another name for the pituitary?
The hypophysis cerebri
How are the pituitary and hypothalamus connected?
Via the infundibulum (pituitary stalk)
Where do the anterior and posterior parts of the pituitary arise from?
- Posterior = neurohypophysis = neuronal (is a swelling of the pituitary stalk distally)
- Anterior = adenohypophysis = epithelial (is upgrowth from root of primative oral cavity)
What are the red and blue circles?
Red= hypophyseal/pituitary fossa
Blue= Spenoid sinus
What is the shelf of dura that covers the roof of the pituitary fossa called?
Sellar diaphragm
What is the median eminence?
The median eminence is the structure at the base of the hypothalamus where hypothalamic-releasing and –inhibiting hormones converge onto the portal capillary system that vascularizes the anterior pituitary gland
How are cells divided up in the anterior pituitary?
cells are divided chromophills- about to secrete hormone/filled with hormone (B) and chromophobes- not fully of hormone (lightly stained)
What are the different releasing/inhibiting factors, the hormone they release and the effects of that hormone for the anterior pituitary?
How are anterior pituitary hormones released?
- Hormones released from the hypothalamus can both promote and inhibit hormone release from the pituitary
- Factors which control release are released from the terminals of hypothalamic nuclei into pituitary portal system, which has vascular sinusoids between secretory crells
What are the different cell types that release hormone in the anterior pituitary?
Do the anterior and posterior pituitary make their own hormone?
Anterior= YES
Posterior= NO
How does the posterior pituitary release hormones?
- Magnocellular neurons originate from the hypothalamus and terminate in the posterior pituitary
- Hormones are synthesized in magnocellular neuron
- Hormones pass down axons bound to glycoproteins through pituitary stalk where they are stored in the distended terminal end of the axon
- Release is controlled by nerve impulses = neurosecretion
What are the hormone pathways that occur in the posterior pituitary?
What are Herring bodies and Pituicytes?
Herring bodies- end of axons from hypothalamus-where hormone is released from, pituicytes- supporting cells
Where does the pituitary get its blood supply from?
Pituitary gets blood supply from superior and inferior hypophyseal artery (branches of the internal carotid artery)
What hormones does the thyroid produce?
Produces T3 and T4, regulates basal metabolic rate
Also releases calcitonin- regulates blood calcium levels
How is the thyroid stimulated?
By secretion of TSH from anterior pituitary
What are the 3 parts of the thyroid?
What arteries supply the thyroid with blood?
Superior thyroid artery (branch of external carotid)
Inferior thyroid artery (branch of subclavian)
How is blood drained from the thyroid?
Superior and middle thyroid veins (drains to internal jugular) and inferior thyroid vein ( drains in subclavian or brachiocephalic veins)
How many parathyroids do people have?
Variable in number, usually 4
What is the function of the parathyroid?
Secretes parathyroid hormone, regulates serum calcium and phosphate levels
What is the blood supply/ drainage to the parathyroid?
Supplied mainly by inferior thyroid artery
Drains to thyroid plexus of veins
What are the different cells present in the parathyroid?
- Chief/ principle cells= make hormone
- Oxyphil cells= unknown functiom
- Adipocytes= lots of fat present
What is the pancreas, and what is its function?
Accessory digestive gland
Produces exocrine and endocrine secretions
What are the endocrine secretions made from the pancreas?
Has pancreatic islets that contain:
- Alpha Cells- glucagon, Raise Blood Glucose
- Beta cells- insulin- Promotes uptake of glucose to lower blood glucose
- Delta cells- Somatostatin, Gastrointestinal function
Where is the pancreas located?
Posterior to stomach, between duodenum and spleen
What is the drainage system from the pancreas?
The venous portal system straight to the liver
What is the shelf of Dura covering the pituitary fossa known as?
Sellar Diaphragm
What structure passes through the sellar diaphragm and connects the pituitary gland to the base of the brain?
Infidibulum
Or pituitary stalk
What are the following labels?
What are the following labels?
Where are the cell bodies, axons and synapses of the magnocellular neurons located?
-Cell bodies: Supraoptic and Paraventricular nuclei of the hypothalamus
-Axons: Travel in the pituitary stalk
-Synapses: Posterior Pituitary
What structure is found immediately below the pituitary fossa?
The sphenoid sinus
What nerve do the superior and recurrent laryngeal nerves both originate from?
The vagus
Which veins do the thyroid veins drain in to?
- Superior and middle thyroid veins – to internal jugular vein
- Inferior thyroid veins – to the brachiocephalic veins.
What is the blood supply to the parathyroid glands?
- Primarily branches from the inferior thyroid arteries, collateral supply from superior thyroid arteries.
What are the letters?
PP: Posterior Pituitary
AP: Anterior Pituitary
P: Pituitary Stalk
O: Optic Chiasm
H: Hypothalamus
V: Ventricle
What are chromophobes and chromophils?
The secretory cells of the anterior pituitary (AP) are traditionally classified into two groups, chromophils and chromophobes, based on their affinity for standard histological dyes. The chromophils are further subdivided into acidophils and basophils, according to their affinity for either acid or basic dyes
What are the different letters?
A=acidophils
B=basophils
Cp= chromophobes
What are the letters on the picture of the thyroid?
F= follicle
S= septa
Follicles contain coloid
What are the different letters?
A: Adipocyte
C: Capillary
P: Chief/Principle cells
O: Oxyphil cells
Where are alpha and beta cells found in the pancreas?
In the pancreatic islet
What hormone do alpha cells secrete, and what does it do?
Secrete glucagon, which raises blood glucose levels
What hormone do beta cells secrete, and what does it do
- Beta cells secrete insulin, which increase glucose uptake and thereby decrease blood glucose levels.
What nucleus extends to the posteriornprituiary to produce vasopressin and what one makes oxytocin?
the supraoptic nucleus which makes vasopressin. (The paraventricular nucleus makes oxytocin).
What blood vessels supply the pancreas?
The pancreas has a rich blood supply, including the great pancreatic artery (celiac trunk -> splenic); the superior pancreaticoduodenals (celiac trunk -> common hepatic -> gastroduodenal) and inferior pancreaticoduodenals (superior mesenteric).
At what vertebrae level do the kidneys lie?
T12-L3
Which kidney is lower and why?
Right is lower due to relationship with liver
What ribs are posterior to the kidneys?
11 and 12
What is superior, inferior and medial to the kidneys?
Medial= renal veins
Superior= adrenal glands
Inferior= colon
What anatomical structures are anterior to the kidney and where are they placed?
Adrenal glands (AG), Liver (L), Duodenum (D), Right and left colic flexures (RCF, LCF), Small intestine (SI), Stomach (S), Pancreas (P)
What is the blood supply of the kidneys?
Supplied by direct branches of the aorta- left and right renal arteries
Left and right renal vein drain into the IVC
What structure does the left renal vein cross over?
The aorta
What are the adrenal glands?
Paired fatty glands at the superior poles of the kidneys
Comprised of the cortex and the medulla
What are the different shapes of the adrenal glands?
Right= pyramidal
Left= semi lunar
What are the differences in the two adrenal glands?
Left is larger than right
Right is stacked in by the IVC, left forms part of the stomach bed
What are the different anatomical relations of the left and right adrenal glands (superior, inferior, anterior, lateral, posterior and medial)?
What arteries supply the adrenal glands?
Superior, middle and inferior adrenal artery
Where does the superior adrenal artery arise from?
From right inferior phrenic artery
Where does the middle adrenal artery arise from?
From the abdominal aorta
Where does the inferior adrenal artery arise from?
From the renal arteries
What is the venous drainage of the left and right adrenal gland?
Left suprarenal veins anastomose with the inferior phrenic vein
Right suprarenal vein is a single vein that drains into IVC or renal vein
How do testes descend through the abdomen?
Descend through the abdomen, pelvis and inguinal canal to reside in the scrotum outside the pelvis
What is the blood supply to the testes?
Supplied from the aorta at L2, and then travel down to scrotum. Called the testicular arteries or gonadal arteries
What is the venous drainage of the testes?
The pampiniform plexus surrounds the testis, left gonadal vein drains to left renal vein and right gonadal vein drains to the ICV
What are the different labels on the histology of the testes?
What are the similarities/ differences in how the ovaries and testes develop?
Both develop high in the abdomen and the descend but the ovaries do not enter the inguinalcanal
What are the anatomical relations of the ovaries (lateral, posteriorly, anteriorly, superiorly and medially)?
Laterally= pelvic brim, suspensory ligament of the ovary
Posteriorly= ureters, internal iliac vessels
Anteriorly= intestines
Superiorly= fallopian tube
Medially= proper ovarian ligament
What is the broad ligament?
Sheet of tissue that covers the ovaries and surrounding structures
Where does the ovarian artery arise from?
The aorta at L2
What ligament does the ovarian artery run through?
Suspensory ligament
Whatplexus of veins surround the ovarian artery?
Pampiniform plexus
Where do the right and left ovarian veins drain to?
Right= IVC at L3
Left= left renal vein
What are the following labels on the histology of the ovary?
What are the anatomical relations of the uterus?
- Anteriorly= vesto-uterine pouch and bladder
- Laterally: Broad ligament (BL), fallopian tubes (FT), ovaries (O), uterine vessels
- Posteriorly: Rectouterine pouch, rectum (R)
- Inferiorly: cervix
- Superiorly: broad ligament, intestines
What is the blood supply of the uterus?
The uterine artery from internal iliac artery
Where does the uterine vein drain to?
The internal iliac vein
What are the different layers of the uterine wall?
Perimetrium, outermost layer
Myometrium, thickest layer and contains smooth muscle and neurovasculature
- Endometrium, innermost layer that is rich in glands and thickens and generates blood vessels. Is shed during mensuration
- Endometrium has two layers basal (which is not shed) and functional
What are the different layers of the endometrium?
What are the different stages of the endomeitium through the cycle?
What hormones does the placenta produce?
hCG, progesterone and oestradiol
What are the differences in the sides of the placenta?
Is smooth on foetal side and rough on maternal side
What vessel does the right renal artery pass behind?
IVC
What vessel does the left renal vein pass in front of?
Aorta
What vessel does the left renal vein pass under?
Superior mesenteric artery
What is nutcracker syndrome?
Compression of the left renal vein between the superior mesenteric artery and the aorta.
Commonly presents as haematuria due to a venous hypertension, resulting resulting in rupture of the thin walled veins in the collecting duct.
What ribs do the kidneys come in contact with?
Left is posteriorly protected by ribs 11 and 12, right only has a relationship with rib 12.
What are the different characteristics of proximal and distal tubules in the kidney?
Distal tubules are lighter staining as they contain fewer vessels and mitchondria than proximal tubules
Histology of the kidney
Where does the superior, middle and inferior adrenal artery arise?
Superior adrenal artery from inferior phrenic artery
Middle adrenal artery from abdominal aorta
Inferior adrenal artery from renal artery
What are the different areas of the adrenal cortex?
Black= capsule
Teal= zona glomerulosa
Blue= zona fasciculata
Green= zona reticularis
Red = medulla
What are the labels?
What are the labels?
What is the pouch of Douglas?
The rectouterine pouch
What is the uterine artery a branch of?
Internal iliac artery
Where does blood from the uterine vein drain into?
Internal iliac vein
What features of the endometrium indication the proliferative and the secretory phases?
Proliferative
o Restricted blood vessels
o Thin endometrial wall
o Flat luminal surface
Secretory
o Thickening of functional layer
o Coiling of glands
o Some saw-toothed glands
What is the outermost layer of foetal cells that completely surrounds the foetus and ALL foetally-derived tissues, and lies adjacent to the maternal tissue?
The chorion – an outer layer formed by trophoblasts and an inner layer formed by somatic mesoderm.
What are the unique features of the maternal and foetal surfaces of the placenta?
Foetal surface is smooth and covered by the chorion. The maternal surface is rough containing a very thin layer of decidua which is of maternal origin and derived from the endometrium.
