Triiodothyronine-I131 Uptake by Bull Spermatozoa.

Abstract
[long dash]The uptake of T3-I13I triiodothyronine-I131 by bull spermatozoa was studied. Trials with frozen semen (-79[degree]C) and stored semen (5[degree]C) indicated that uptake of T3-I131 by spermatozoa was related to viability of the spermatozoa. Uptake of T3-I131 by spermatozoa was independent of the amount of T3 added to the diluted semen within the range studied The composition of the spermatozoa diluent greatly influenced uptake of T3-I131 by spermatozoa. Washed spermatozoa suspended in a 3% sodium citrate diluent had a much greater uptake of T3-I13I than washed spermatozoa suspended in an egg yolk-sodium citrate diluent, indicating that diluent constituents may compete with the spermatozoa for uptake or binding of T3-I13I.