Effect of short-term and long-term lithium treatment on uptake and retention of iodine-131 in rat thyroid.
No significant change occurred in the uptake by the thyroid of male Wistar rats of a standard dose of carrier-free 131I administered intraperitoneally and its retention by the thyroid, as measured by biological and effective half-life, after feeding these rats a powdered pelleted diet containing lithium carbonate (1.1 g per kg of diet) for 7 days. However, continuing this diet for 10 days inhibited thyroid uptake and increased the retention of 131I. Uptake remained suppressed for up to 4 months after lithium treatment and continuing this treatment for 6 months did not result in any significant change in 131I uptake by the thyroid. Lithium treatment for 10 days increased the biological and effective half-life of 131I in the thyroid and this increase continued for the 6 months treatment period. The dose of 131I delivered to the thyroid was significantly lower after 10 days and 1 month of lithium treatment but there was no change in this dose after 2 and 4 months of treatment. However, there was a significant increase after 6 months.
Dhawan
D
D
Department of Biophysics, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
Sharma
R R
RR
Sharma
R
R
Dash
R J
RJ
D000818:Animals; D006207:Half-Life; D007457:Iodine Radioisotopes; D008094:Lithium / Q000493:pharmacokinetics / Q000494:pharmacology*; D016651:Lithium Carbonate; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013961:Thyroid Gland / Q000187:drug effects / Q000378:metabolism*; D013997:Time Factors
D007457:Iodine Radioisotopes; D016651:Lithium Carbonate; D008094:Lithium