Question

Scientists are running pharmacokinetics study on hormone X. They gave a test subject an initial IV injection of 100 mg/mL of hormone X and monitored the patient over time. After 1.5 hours, blood test analysis showed that only 30 mg/mL remained in the blood Urine output over this time frame was 5 mL and analysis of the urine revealed that it had a concentration of 65 mg/mL of hormone X. Further analysis of the blood determined, that the fraction of unbound hormone X was 1 (100%).

Based on these results: 1. How would hormone X be synthesized in a cell?

2. What type of receptor would Hormone X bind to at the target cell?

3. Calculate the metabolic clearance rate (show all work):

Answer 1

1). Hormone X is a water soluble hormone because most of it is excreted via the urine and it is not bound to plasma proteins. The lipid or steroidal hormones are not dissolved in plasma, so they always need some carrier proteins like albumin or other hormone specific binding molecules.

The water soluble hormones include both the amino acid derivates and protein hormones, both of which are synthesized from the amino acids in the cell.

2). As the water-soluble hormones cannot pass through the plasma membrane, they bind to the plasma membrane receptors.