Syphilis and drugs of abuse.

In summary, treponemal infections in hamsters treated with THC were slightly enhanced in comparison with vehicle controls. A greater degree of enhancement was exhibited in rabbits; treponemes proliferated more readily during treatment with THC than in control animals. Contrary to expectations, this occurred even in lesions which were not developed fully, i.e., were not ulcerated. Thus, treponemes were present in aspirates earlier during infection and from sites which had received smaller inocula of treponemes in these rabbits than in controls. Lesions in control groups developed ulcerations earlier than did the THC-groups, but treponemes were too scarce to be seen in pre-ulcerative lesions in these animals. It appears that THC-treatment enhanced infection with T. pallidum. It may be that in the local skin lesion, macrophages which are vitally important in early host responses to treponemal infection may not have been functioning optimally and mediators of tissue damage may not have been produced and, therefore, ulceration was delayed in spite of enhanced infectivity of the treponemes.