Suger 1 Flashcards
Where does the inguinal canal travel?
From deep inguinal ring in transversalis fascia to superficial inguinal ring in external oblique aponeurosis
What does the inguinal canal convey?
M - spermatic cord
F - round ligament of uterus
What is the floor of the inguinal canal formed by?
Inguinal ligament
What is a hernia?
A protrusion of organs/fascia through the wall of the cavity that contains them
What is an indirect hernia?
Peritoneal sac enters canal through deep inguinal ring
(gains same 3 coverings as it enters)
(more common)
What is a direct hernia?
Sac bulges into canal via posterior inguinal wall
(due to weakening in abdominal musculature)
(sac from area medial to epigastric vessels)
What are the 3 layers covering the spermatic cord?
One for each layer of muscle in abdominal wall
Internal
External
Transverse
What is contained within the spermatic cord? (3x5)
3 arteries - testicular, cremasteric, to vas deferens
3 veins - as above
3 nerves - ilioinguinal, genitofemoral, sympathetic & afferent fibres
3 others - vas deferens, lymphatics, pampiniform plexus
3 coverings - external spermatic, cremasteric, internal spermatic fascia
What do the testes produce?
Spermatozoa
Testosterone
What is the tunica vaginalis?
Peritoneal sac that partially covers testes
What are the parts of the epididymis?
Head - formed by convergence of efferent tubules
Body
Tail
What is the vas deferens?
Muscular tube
Transports sperm from testes to ejaculatory ducts
Continuous from inferior tail of epididymis
What is the tunica albuginea?
A fibrous capsule that fully encloses each testes
Penetrates into parenchyma to divide it into lobules
What is the scrotum?
Fibromuscular cutaneous sac that the testes sit within
What is the dartos muscle?
Lies immediately beneath skin of scrotum & helps in temperature regulation by wrinkling skin
What is the path of the vas deferens?
Tail of epididymis > inguinal canal in spermatic cord > deep ring > between bladder & urethra > seminal vesicle duct
What are the 3 muscles of the wall of the vas deferens?
Inner longitudinal
Middle circular
Outer longitudinal
What is the ejaculatory duct formed by?
Confluence of vas deferens & seminal vesicle duct
What does the ejaculatory duct drain into?
Prostatic urethra
What are the secretions of the seminal vesicle composed of? (4)
Alkaline fluid
Fructose
Prostaglandins
Clotting factors
What does the prostate gland secrete?
Proteolytic enzymes that break down clotting factors in semen to allow it to remain fluid in the female tract
What are the 3 parts of the penis?
Root
Body
Glans - continuous with corpus spongiosum
What are the 3 cylinders of erectile tissue?
2x corpus cavernous
Corpus spongiosum
What are the 2 main roles of the penis?
Sexual intercourse
Miturcation
What are the 3 erectile tissues in the root of the penis?
2x crura
Bulb
What are the 2 muscles of the root of the penis?
Bulbospongiosus x2 - contracts to empty spongy urethra of residual
Ischiocavernosus x2- contracts to help maintain erection
What are the 3 main parts of the male urethra?
Prostatic
Membranous
Spongy
What are the 2 fascial coverings of the penis?
Deep fascia of the penis (more superficial) Tunica albuginea (around each cavernous)
What are the 2 ligaments of the root of the penis?
Suspensory
Fundiform
What is the arterial supply to the penis?
Dorsal to penis
Deep to penis
Bulbouretheral
(all branches of internal pudendal artery)
What is the innervation to the penis?
S2-4 spinal cord segments
Sensory & sympathetic by dorsal nerve of penis (branch of pudendal)
Parasympathetic by cavernous nerves (from prostatic nerve plexus)
What are the 3 main functions of the pelvic floor?
Support of abdominopelvic viscera
Resistance to increases in intra pelvic/abdominal pressure
Urinary & faecal continence
What are the 2 main holes in the pelvic floor?
Urogenital hiatus
Rectal
What are the 4 main muscles of the pelvic floor?
Levator ani muscles: puborectalis pubococcygeus iliococcygeus Coccygeus
What are the borders of the urogenital triangle?
Pupic synthesis
Ischiopubic rami x2
What does the urogenital triangle contain? (6)
Deep perineal pouch Perineal membrane Superficial perineal pouch Deep perineal fascia Superficial perineal fascia Skin
What is the glomerular filtration rate?
Amount of fluid filtered from blood by renal corpuscle per unit time
What is the GFR determined by? (3)
Glomerular filtration pressures
Permeability of glomerular capillary wall
Surface area available for filtration
What is the pressure of glomerular filtration under control of?
Neural & hormonal inputs
What does constriction of afferent/dilation of efferent arterioles do to the GFR?
Decrease
Overall decrease in pressure at glomerulus
Reduction of blood hydrostatic pressure in capillaries
What does neuroendocrine input to the intraglomerular mesangial cells that surround the glomerular capillaries do?
Contract when stimulates
Reduce SA for filtration
Decrease GFR
What is the equation for the amount filtered by the glomerulus?
Amount filtered = GFR x plasma concentration
How does reabsorption by diffusion occur?
Water reabsorption from tubule
Relative concentrations of various substances in filtrate increase
Substances diffuse across tight junctions between epithelial cells & into interstitial fluid
Diffuse from interstitial to peritubular capillaries
How does reabsorption by mediated transport occur?
Linked to reabsorption of Na+ ions
Cotransported substance moves against concentration gradient by secondary active transport by cotransporter protein on luminal membrane
Also transports Na+ down its concentration gradient into cell
What are the transporters in each part of the nephron? (4)
PCT - NKC (sodium-potassium co-transporter)
Loop of Henle - NKCC2 (sodium-potassium-chlorine co-transporter 2), loses K keeps Cl & Na
DCT - NCC (sodium-calcium co-transporter), loses K, keeps Na & Ca
CD - EnaC (epithelial sodium channel), keep or secrete K
Why is there a transport maximum for mediated transport mechanisms?
Binding sites of membrane proteins become saturated y the substances they are helping to transport
Define osmolarity
Number of moles of a solute in a solution per L of solvent
Define osmolality
Number of moles of a solute in a solution per kg of solvent
What is osmolarity affected by that osmolality isn’t?
Changes in water temperature & pressure as these change the volume of the solution
Where is ADH synthesised & released from?
Synthesised in hypothalamus
Released from posterior pituitary gland
How does ADH influence the permeability of the luminal membranes of the collecting ducts?
Enters interstitial fluid
Binds with receptors on basolateral membrane of epithelial cells
Helps produce secondary messenger cAMP
cAMP activates protein kinase A (PKA)
Results in fusion of vesicles containing AQP2 aquaporin channels with luminal membrane
More water can now enter cell by osmosis through channels
What are the 3 inputs to the juxtaglomerular cells that stimulate the release of renin?
Renal sympathetic nerves - stimulated by CV baroreceptors that detect drop in BP
Infrarenal baroreceptors - cells less stretched when drop in BP
Macula densa - between thick ascending & distal tubules, sense low Na+ concentration
What does atrial natriuretic peptide act to do?
(decreases BP by vasodilation)
Secreted from heart atria
Increase Na+ excretion by:
Inhibiting reabsorption
Increasing GFR by causing vasoconstriction of efferent arteriole
Inhibiting secretion of aldosterone
This reduces BP/plasma volume as water follows Na+ by osmosis
What is the pressure natriuresis mechanism?
An increase in urinary sodium loss
By increase in renal perfusion pressure due to increase in arterial BP
Where is angiotensinogen secreted from?
Liver
Where is ACE secreted from?
Lungs
Where is renin secreted from?
Kidneys
Where is aldosterone secreted from?
Adrenal gland
Cortex
What is renin’s role in the RAA system?
Converts angiotensinogen to angiotensin I
What is ACE’s role in the RAA system?
Converts angiotensin I to angiotensin II
What are the roles of angiotensin II in the RAA system? (5)
Sympathetic activity increases
Tubular Na+ & Cl- reassertion, K+ excretion, H2O retention
Aldosterone secretion (also causes ^)
Arteriolar vasoconstriction, increase in BP
ADH secretion from posterior pituitary gland
What is ADH’s role in the RAA system?
Increases H2O reabsorption from the collecting duct
What is the overall role of the RAA system? (3)
To retain water & salt
To increase circulating volume
To overall increase BP
What causes renin to be released? (3)
Drop in BP/fluid volume
Decrease in renal perfusion
Juxtaglomerular apparatus & macula densa activated
What are the 3 mechanisms for the controls of Na+ reabsorption?
RAA system
ANP
Pressure natriuresis
What does parathyroid hormone do in the kidney?
Blocks reabsorption of phosphate in PT
Promotes calcium reabsorption in Henle, DT, CT