Adh Secretion Lab Report

Discussion The results of this experiment for the hypotonic treatment group did support the tested hypothesis that urine production rate should increase, while salt concentration and specific gravity of urine should decrease for this group. For the isotonic treatment group, the tested hypothesis was supported in that the specific gravity and salt concentration went up slightly, but was not supported in that the the urine production rate did not greatly increase over time. The findings for the hypertonic group supported the hypothesis in that the salt concentration and specific gravity went up, but the urine output rate did not decrease significantly as was hypothesized. Figures 1, 2, and 3 convey the data that were was used to assess the tested …show more content…
This is done by the insertion of aquaporins primarily into the collecting duct, which is normally impermeable to water. Then, water can move out of the collecting duct and be reabsorbed into the interstitial fluids. ADH secretion is regulated by both osmoreceptors in the hypothalamus and atrial stretch receptors, invoking a negative feedback loop to control osmolarity of the blood plasma as well as vascular volume. If there is a decrease in plasma osmolarity, the osmoreceptors in the hypothalamus will signal for a decrease the secretion of ADH form the posterior pituitary. This means there will be reduced permeability to water in the collecting duct, and less water reabsorption (Sherwood, 2013). On the other hand, if more ADH is secreted, the kidneys can concentrate the urine up to 1200 mOsmols to conserve water (Baker, 1995). Additionally, with a large consumption of a hypotonic drink, there will be an increase in vascular volume, leading to atrial stretch which is sensed by atrial stretch receptors. This will also cause less ADH secretion, effectively lowering vascular volume since more water will be excreted in the urine. Through these two negative feedback loops, ADH can manage fluid