PSORIATIC HYPERPLASIA: SOME MEASUREMENTS.

Single psoriatic lesions were analysed planimetrically and autoradiographically after ³H-thymidine labelling. The results indicate maximum alterations of epidermis and papillary body in the centre of a lesion. Epidermal volume values are elevated at the periphery while the papillary body is still normal. After stripping, the proliferative activity of the peripheral epidermis increases in proportion to epidermal volume, while no stimulatory effect can be exerted in the centre of a lesion. Comparison of several lesions reveals large differences for volume values and between single rete pegs for ³H-thymidine labelling. The role of an epidermal defect in evoking the changes is discussed. [ABSTRACT FROM AUTHOR]