Nov 27 - Anatomy of the Retroperitoneum and Renal System Flashcards
What covers the retroperitoneal structures?
The posterior parietal peritoneum
What is the pancreas?
It is an endocrine gland and an exocrine gland
Describe endocrine aspect of the pancreas
There are pancreatic islands that secrete insulin, glucagon and somatostatin
Describe the exocrine aspects of the pancreas
It secretes trypsin, chymotrypsin and lipases through the pancreatic ducts. The pancreatic ducts and the common bile duct open into the lumen of the duodenum at the papilla vateria
How can the papilla be obstructed? What can result from an obstruction?
It can be obstructed by a bile stone, which may cause pale, fatty feces and/or pancreatitis (autolysis)
What happens in the duodenum?
It neutralizes acidic chymus from the stomach (brunner glands). It receives pancreatic secretions and receives bile
Name the unpaired branches of the abdominal aorta
The celiac trunk, the superior mesenteric, the inferior mesenteric and the median sacral branches
Name the paired branches of the abdominal aorta
The inferior phrenic, the suprarenal, the renal, the lumbar, the ovarian/testicular and the common iliac branches
Name the three vascular planes of the abdominal aorta
The unpaired branches (supply the organs of the abdominal cavity), the paired branches to internal organs (which don’t go into the abdominal cavity) and the paired branches to the wall of the trunk
Describe the lymphatic system in the retroperitoneal space
The retroperitoneal space contains many lymph nodes which collects lymph from the lower extremities, the abominal organs and the wall of the trunk. All lymph collects in the cysterna chyli just inferior to the diaphragm and ascends into the thoracic duct which empties into the left venous angle
What is the biggest lymph duct in the body?
The thoracic lymph duct
Name the blood supply of the adrenal glands?
They derive from the inferior phrenic arteries, abdominal aorta and the renal arteries
What does the cortex of the adrenal gland produce?
Glucocorticoids (cortisol), mineralocorticoids (aldosterone) and weak androgens (dehydroepi-androsterone; in women, the cortex of the adrenal glands is the only source of androgens in females whereas males also produce androgens in the testicles)
What does the medulla of adrenal gland produce?
Catecholamines: adrenaline (epinephrine) and some noradrenaline (norepinephrine)
How is the adrenal gland involved in the short term stress response?
Sympathetics innervating the medulla of the adrenal gland stimulate the release catecholamines into the blood circulation. It is a fast, temporary response
How is the adrenal gland involved in the prolonged stress response?
Adrenocorticotropic hormone (ACTH) secreted by the anterior pituitary stimulates the release of glucocorticoids and mineralcorticoids from the cortex of the adrenal gland. It is a slow, lasting resposne
Name the four urinary organs
The kidney, the ureter, the bladder and the urethra
What is found in the hilum of the kidney?
The renal arteries, the renal vein and the ureter
What is the most posterior in the hilum of the kidney?
The ureter
What is the most anterior in the hilum of the kidney?
The renal veins
What protects the kidneys?
The renal fascia and the fat capsule
What is the pelvis renalis?
Aka the renal pelvis
It collects the urine from the renal papillae and connects to the ureter
What are the functions of the kidneys?
Blood filtration, reabsorption and excretion (also electrolyte balance, blood volume regulation)
What do the kidneys produce and secrete?
Renin, erythropoietin (EPO) and 1,25-(OH)2 Vitamine D3
What is renin?
It is a hormone that participates in the renin-angiotensin-aldosterone system (RAAS), which regulates the arterial blood pressure
How does renin function?
It activates angiotensinogen into angiotensin I, which is further converted into the angiotensin II, which is a vasoconstrictor and increases the aldosterone secretion. It reduces the plasma sodium concentration and increases epinephrine
Describe the ureter
A retroperitoneal muscular tube of 20-30 cm in length. It has 3 layers of smooth muscles that facilitate peristalsis. It crosses the iliac vessels anteriorly. It enters the urinary bladder at the trigone
Describe the aspects of the male ureter
It is lateral and inferior to the ductus deference and it joins the bladder superior to the seminal vesicles
Describe the aspects of the female ureter
It crosses beneath the uterine artery (“water” under the “bridge”)
Name the blood supply of the ureter
Variable branches of the ovarian, common and internal iliac artery
Name the three constrictions of the ureter
The exit from the hilum
The crossing of the iliac blood vessels and the pelvic brim
The entrance into the bladder
Describe the urethra in females
The urethra is tightly connected via connective tissue to the anterior wall of the vagina; they pass together through the pelvic diaphragm, perineal membrane and external urethral sphincter
Describe the membranous part of the urethra in males
The least distensible and passes through the external urethral sphincter. It’s the most vulnerable during insertion of urethral catheters and to injury
Describe the prostatic urethra
The widest part and contains the openings of the ejaculatory ducts and of the prostatic ductules. It can be obstructed by proliferating tissue in benign prostatic hypertrophy (BPH)
Describe the spongy urethra
It is within the corpus spongiosium of the penis
Where is the bladder found?
Posterior to the pubic symphysis
What muscles surrounds the bladder?
The detrusor muscle (smooth muscle), which is parasympathetically innervated
What happens when the bladder fills in terms of its position?
A filled bladder extends and rises up to 10 cm above the pubic symphysis pushing its peritoneal lining cranially further towards the umbilicus
What is the prostate gland?
The largest accessory gland of the male reproductive system (chestnut-sized). It is located between the bladder and the urogenital diaphragm. It develops 30-40 individual glands originating from the urethral epithelium. Individual ducts open into the prostatic part of the urethra. Glands embedded in a fibromuscular stroma containing smooth muscles
Describe prostatic secretions
Prostatic secretions accound for 20-30% of ejaculate volume. Secretions are acidic (pH 6.4), serous and milky. They contain immunoglobins, acidic phosphatase, proteases, fibrinolytic enzymes, zinc, prostaglandins, citrate (acidic pH), spermin
Describe the position of the prostate gland
It is in the pelvis beneath the urinary bladder, just above the pelvic floor and surrounding the proximal part of the male urethra
What forms the ejaculatory duct?
The seminal vesicle and the ampulla of the vas deferens join to form the ejaculatory duct which enters the prostatic urethra
What supplies the prostate and seminal vesicles with arterial blood?
Arterial supply originates from the inferior vesical artery
Describe the venous drainage of the prostate and the seminal vesicles
Venous blood drains to the vesicoprostatic venous plexus around the base of the urinary bladder
Name the three zones of the prostate
The transition or central zone
The periurethral zone
The peripheral zone
What zone is susceptible to prostate cancer?
The peripheral zone
What zone is susceptible to benign prostatic hyperplasia
The central zone
What is the importance of the central zone?
It marks the postero-medial glandular tissue located between the two ejaculatory ducts
Name the nerves of the lumbar plexus
The iliohypogastric nerve, the ilioinguinal nerve, the genitofemoral nerve, the obturator nerve, the femoral nerve and the lateral cutaneous nerve of the thigh
Name the nerves of the sacral plexus
The sciatic nerve, the superior gluteal nerve, the inferior gluteal nerve, the pudendal nerve, the posterior cutaneous nerve of the thigh and the direct branches to muscles of the pelvis
The somatic nerves of the lumbar and sacral plexus provide motor innervation to what?
The muscles of the anterolateral abdominal wall, the muscles of the lower extremity, the gluteal muscles, the pelvic floor muscles and the muscles of the perineum
The somatic nerves of the lumbar and sacral plexus provide sensory innervation to what?
The skin of the anterolateral abdominal wall, the skin of the lower extremity, the skin of the gluteal region, the skin of the perineum and the mucosa of the lower urethra, vagina, vestibule and anal canal
The autonomic nerves of the pelvis provide motor, secretory and sensory innervation to what?
The pelvic viscera
The autonomic nerves of the pelvis provide sympathetic innervation from the sacral sympathetic trunk to what?
The skin of the lower extremity, gluteal region and perineum
The autonomic nerves of the pelvis provide parasympathetic innervation from the S2-S4 parasympathetic centre to what?
The smooth muscle of the rectum and the corpora cavernosa of the penis/clitoris
