RU 28318 also known as OXPRENOATE is a mineralocorticoid receptor (MR) antagonist, inhibiting aldosterone production and secretion. RU 28318 has been studied in normal and diabetic rats. It was revealed, that in combination with angiotensin converting enzyme inhibitors, RU 28318 was the most effective at improving -dP/dt (a measure of diastolic function) and attenuated cardiac dysfunction in diabetes.

Ortho-iodohippurate (also known IODOHIPPURATE) as is used for the determination of effective renal plasma flow. It is a halogen derivative of a compound normally found in human urine, and as the end product of a process of detoxification is synthesized in the body. This compound is nontoxic, when administrated intravenous. In patients with normally functioning kidneys, 85% of the ortho-iodohippurate may be found in the urine 30 minutes after intravenous injection. It is eliminated mainly by tubular secretion.