Cholera toxin: mitogen for Harderian glands of golden hamsters

1. Within 2 days, a single injection of 10 micrograms cholera toxin induces a 6-20-fold increase in mitotic activity in the Harderian glands of male and female golden hamsters. 2. Neither hypophysectomy nor ovariectomy had any influence on this response. 3. The cellular proliferation does not appear to involve cAMP nor is it the result of stress, nor a release from an early mitotic block. 4. Nuclear polyploidy increases within a few hours after treatment. 5. DNA density per unit area increases within 24 hr and is maintained for at least 3 days.