Countercurrent multiplication:
F. 26-16
Transport maximum (T
m
)
– If nutrient concentrations rise in tubular fluid:
•
Reabsorption rates increase until carrier proteins are
saturated. It reaches the transport maximum.
Renal Threshold :
Is the plasma concentration at which a specific
compound or ion begins to appear in urine.
•
Renal Threshold for Glucose
–
Is approximately 180 mg/dL
–
If
plasma glucose
is greater than 180 mg/dL:
• T
m
of renal tubular cells is exceeded
•
Glucose appears in urine
–
Glycosuria
Clinic terms:
1. Proteinuria: protein in urine.
2. Hematuria: blood cells in urine
3. Glucosuria: glucose in urine
Diuretics
: (water pills)
drugs that increase the loss of water in urine to
decrease blood volume, blood pressure and edema.
(side effects of high dose: dehydration, cardiac arrest)
Ureters:
1. Extend from renal pelvis to the urinary bladder.
2. Move the urine by peristalsis of smooth muscles.
Urinary Bladder:
1.
Supported by middle & lateral ligaments
(derived from 2 umbilical arteries of fetal).
2. Rugae: folds of mucosa lining in the inner wall
3. Very thick muscularis layer called “
detrusor muscles
”.
4. Trigone: act as a funnel
5. Internal urethral sphincter (smooth m.): involuntary,
by parasympathetic n.
6. External urethral sphincter (skeletal m): voluntary control.
F. 26-19a
Ureters:
(Transitional epithelium)
1. Extend from renal pelvis to the urinary bladder.
2. Move the urine by peristalsis of smooth muscles.
Urinary Bladder:
(Transitional epithelium)
1.
Supported by middle & lateral umbilical ligaments
(derived from 2 umbilical arteries of fetal).
2. Rugae: folds of mucosa lining in the inner wall
3. Very thick muscularis layer called “
detrusor muscles
”.
4.
Trigone
: act as a funnel
5. Internal urethral sphincter (smooth m.): involuntary,
by parasympathetic n.
6. External urethral sphincter (skeletal m): voluntary control.
Fetus: Umbilical artery
F. 26-18c
.
F.26-19b
Urination (micturition Reflex):
1. Stretch receptors in the wall of bladder.
2. Afferent & efferent reflex (in the spinal cord)
3. Thalamus and cerebral cortex (voluntary control)
** Incontinence:
inability to control urination due to damage
of internal or external urethral sphincter,
pelvic nerve, spinal cord, CNS or prostate gland.
F. 26-20
***
The greater the Specific Gravity
the higher concentration of urine.
Dialysis : treatment for chronic renal failure
Pyelogram
: (pyelo- = kidney)
An image of the renal system by i.v. injection of dye
and an X-ray.
Renal obstruction:
1.
Casts
: solid fragments of blood clots, epithelium, lipids
and other materials.
Small amount of casts is normal
and they can be eliminated in urine.
