SHolroydAtWeilCornellMedQatar/Urology/Kidney/Tubules/WaterChannels/EffectOfIncrease
| With an increase in the synthesis, secretion, and blood concentration of vasopressin (anti-diuretic hormone, ADH), the number of water channels increases. |
Prior to vasopressin (ADH) increasing (at baseline), we will make the assumption that the subject is in homeostasis with normal plasma and urine osmolarities (isotonic) and volumes.
Step 1: Suppose that the synthesis, secretion, and blood concentration of vasopressin (ADH) increases.
Step 2: The water channel-increasing effect of vasopressin (ADH) is increased, thereby increasing the number of water channels. This increases the reabsorption of water by the kidney.
Step 3: The ratio of Na+ to water entering the plasma due to reabsorption decreases. This decreases plasma osmolarity (hypotonic). Because a lower ratio of Na+ to water leaves the tubule due to reabsorption, the fluid remaining in the tubule has a higher osmolarity (hypertonic). Also, with an increase in water reabsorption, there is less water remaining in the tubule. Overall, the urine becomes more concentrated (hypertonic) and lower in volume.
Challenge Quiz
With an increase in the synthesis, secretion, and blood concentration of vasopressin (anti-diuretic hormone, ADH), the number of water channels in the kidney increase decrease .
With an increase in the synthesis, secretion, and blood concentration of vasopressin (anti-diuretic hormone, ADH), causes water reabsorption by the kidney to increase decrease .
With an increase in the synthesis, secretion, and blood concentration of vasopressin (anti-diuretic hormone, ADH), causes urine volume to increase decrease .
With an increase in the synthesis, secretion, and blood concentration of vasopressin (anti-diuretic hormone, ADH), causes urine osmolarity to increase decrease .
With an increase in the synthesis, secretion, and blood concentration of vasopressin (anti-diuretic hormone, ADH), causes plasma osmolarity to increase decrease .
The effect of increasing in vasopressin (anti-diuretic hormone, ADH) is to contract uterine smooth muscle decrease plasma osmolarity .
The effect of increasing in vasopressin (anti-diuretic hormone, ADH) is to increase decrease the plasma osmolarity .