A sulfhydryl-containing analog of proline with antihypertensive activity and potential antineoplastic activity. Captopril competitively inhibits angiotensin converting enzyme (ACE), thereby decreasing levels of angiotensin II, increasing plasma renin activity, and decreasing aldosterone secretion. This agent may also inhibit tumor angiogenesis by inhibiting endothelial cell matrix metalloproteinases (MMPs) and endothelial cell migration. Captopril may also exhibit antineoplastic activity independent of effects on tumor angiogenesis. or A device used to look at the inside of the intestines and other parts of the digestive tract. It is a capsule that is about the size of a large pill, with a lens, a light, a camera, a radio transmitter, and a battery inside. The patient swallows the capsule and it takes pictures as it travels through the digestive tract. The pictures are sent to a small recorder that is worn on the patient’s waist or shoulder. The pictures are then viewed on a computer by the doctor to check for signs of disease. The capsule endoscope passes out of the body during a bowel movement. Also called wireless capsule endoscope.