“…The B-enzyme in the bovine pituitary gland displayed a single sedimentation constant (3.3 S) as in adrenal gland and testis, whereas, in the anterior lobe of rat pituitary glands, multiple S-Values of the B-enzyme (3.3 S, 7.3 S and 12 S) were observed and the activity of each fraction increased upon pituitary cell hyperfunction. Similar results were obtained in human and rat thyroid glands (Nagasaka, Yoshida, Nakai, Ohyama, Iwase, Ohtani, Shinoda, Masunaga and Nakagawa 1988b;Nagasaka et al 1988a), namely that the B-enzyme from human thyroid glands sedimented at 3.3 S, whereas that in rat thyroids sedimented in three activity peaks, 3.3, 7.3 and 12 S, all of which had characteristics of the B-enzyme. It is unlikely that exonuclease coexists with the B-enzymes in multiple Svalues (Nagasaka, Yoshida, Ohyama, Masunaga, Kato, Suzuki, Itoh and Kawabe 1990).…”