Saliva as a medium for chronobiological studies: its particular potential in steroid endocrinology.

This paper indicates the potential of saliva as a medium for chronobiological studies. It has principally focussed on the work of the Tenovus Institute for Cancer Research, at the University of Wales College of Medicine over the past decade or more, particularly for steroid hormones, so as to give an authoritative viewpoint based on practical experience. The article discusses issues ranging from technical to clinical aspects of hormone assay in saliva, showing disadvantages and limitations of use. Increasingly, many other investigators are developing and applying assays for salivary steroids and it is timely that such assays become tools in the hands of the chronobiologist. The clinical-biochemical importance of saliva resides also in the fact that in its context it is possible to assay enzymes, toxic substances and drugs.