Percent uptake of $sup 131$I radioactivity in some organs from $sup 131$I- 19-iodocholesterol as adrenal tumor localizing agent

Journal Article · Mon Oct 01 04:00:00 EDT 1973 · Nippon Naibumpi Gakkai Zasshi, v. 49, no. 10, pp. 1245-1253

OSTI ID:4327996

Fukuchi, S; Nakajima, K; Takenouchi, T; Tsuchida, S; Ogawa, H

A group of Wistar rats, after intravenous injection with a dose of 10 mu Ci/100 gm body weight of /sup 131/I-19-iodocholesterol, was sacrificed. The effective half-life of /sup 131/I-19-iodocholesterol in rats was 8.80 days in thyroid and adrenals, 1.10 days in liver, 1.14 days in blood, 1.24 days in lungs, 1.81 days in kidneys, 2.19 days in testes, and 3.52 days in ovaries. After the adnninistration of/sup 131/I-19-iodocholesterol in two cases of primary aldosteronism, the radioactivity in stools and urine was estimated and the biological half-life of the compound was calculated. The biological halflife of the /sup 131/I-19-iodocholesterol is 2.25 to 2.60 days, and by calculation, the effuctive half-life is 1.77 to 1.98 days. The total-body absorbed radiation dose from the /sup 131/I then becomes 0.60 to 0.67 rad per millicurie dose of /sup 131/ I-19-iodocholesterol (assuming a 70.0 kg patient). The adrenal adenoma of primary aldosteronism was removed and counted S days after injecting 1.2 mCi of / sup 131/I-19-iodocholesterol. The adenoma weighed 2.1 g and was easily visualized; it contained 0.21% of radioactivity and 115 times the rcdioactivity in blood. Most radioactivity in the adrenal adenoma was detected as /sup 131/I- 19-iodocholesterol or its ester. The urine excreted on the fourth day after injection contained 3.22 and 5.70% of radioactivity injected in two cases of primary aldosteronism and 1.15% in a case of Cushing's syndrome caused by adrenal adenoma. A part of the urine was incubated for 24 hours after adjusting pH to 1.0 with Hbl and the other part was hydrolyzed with BETA -glucuronidase after adjusting pH to 8.8. after the incubation, the urine was extracted with dichloromethane, which was then dried. Most of the radioactivity in the urine was found in the aqueous phase, and less a 0.1% in the dichloromethane phase. The results suggest that most of the radioactivity in the urine could be accounted for as inorganic iodide, not as adrenocortical steroid. (auth)

• Research Organization: Tohoku Univ., Sendai
• NSA Number: NSA-29-021235
• OSTI ID: 4327996
• Journal Information: Nippon Naibumpi Gakkai Zasshi, v. 49, no. 10, pp. 1245-1253, Journal Name: Nippon Naibumpi Gakkai Zasshi, v. 49, no. 10, pp. 1245-1253; ISSN NNGZA
• Country of Publication: Japan
• Language: Japanese

Related Subjects

*ADRENAL GLANDS-- RADIONUCLIDE KINETICS
*BLOOD-- RADIONUCLIDE KINETICS
*IODINE 131-- UPTAKE
*KIDNEYS-- RADIONUCLIDE KINETICS
*LIVER-- RADIONUCLIDE KINETICS
*LUNGS-- RADIONUCLIDE KINETICS
*OVARIES-- RADIONUCLIDE KINETICS
*TESTES-- RADIONUCLIDE KINETICS
*THYROID-- RADIONUCLIDE KINETICS
CHOLESTEROL
FECES
N48720* --Life Sciences--Nuclide Kinetics & Toxicology-- Animals
N48830 --Life Sciences--New Tracer Techniques--Other
RADIATION DOSES
RADIOACTIVITY
RATS
URINE