MEASUREMENT OF ACTIVIN-B IN HUMAN SALIVA AND LOCALIZATION OF ACTIVIN SUBUNITS IN RAT SALIVARY-GLANDS

The present paper is the first report to demonstrate that measurable a mounts of activin B are secreted into the saliva. The results show wid e fluctuations in activin B concentrations during the menstrual cycle with peak values detected at the follicular phase. Estrogen replacemen t therapy was found to increase salivary activin B levels in post-meno pausal subjects. The concentration in males was negligible. These data suggest that activin B concentrations in the human saliva may be unde r hormonal regulation and propose that salivary activin B measurements may prove useful in investigating the as yet less well defined local and/or physiological roles of activin B. The present paper reports, in addition, the immunohistochemical localization of activin/inhibin sub units in the duct systems of the rat submandibular, sublingual and par otid salivary glands. (C) 1996 Academic Press, inc.