DIFFERENCE IN GLYCOHISTOCHEMICAL LECTIN STAINING OF COLLAGEN-FIBERS IN THE CORPORA CAVERNOSA OF NORMAL AND IMPOTENT MEN

The objectives of this study were to investigate the value of glycohis tochemical staining with three lectin types specific to a particular g lycan structure (Arachis hypogaea [PNA], Triticum vulgare [WGA], and c oncanavalin A [Con A]) as a method of defining possible changes in the collagen structure in the corpora cavernosa in potent and impotent me n. The study group consisted of 4 normal potent men and 22 men with va rious etiologies of impotence. The quantitative histochemical measurem ents were performed by means of a cell image processor. Two variables for each of the three types of lectins were studied. These were the me an optical density (MOD), which relates to glycohistochemical staining intensity, and the labeling index (LI), which is positively related t o the percentage of immunostaining. Only WGA staining made it possible to discriminate significantly between the normal and pathological gro ups under study. The two parameters (LI, MOD) were significantly highe r in the case of WGA staining in the normal group (P = 0.004 and 0.013 , respectively). In contrast, only the mean LI value, in the case of t he psychogenic and venogenic patients, reached a level of statistical significance (P = 0.005 and 0.001, respectively), when it increased fr om PNA through WGA to Con A histochemical staining. The two variables (LI, MOD) changed markedly from PNA through WGA to Con A in the arteri ogenic patients (P = 0.003 and P < 0.001, respectively). WGA is of dia gnostic value in distinguishing between normal and abnormal collagen i n the corpora cavernosa. The difference in the lectin staining of the other groups, particularly the arteriogenic group, may be attributed t o alterations in the glycosylation of the procollagen that are probabl y due to changes in the partial pressure of oxygen (PO2) level, an imp ortant cofactor in normal glycosylation. WGA staining may therefore be used as a marker to distinguish true psychogenic patients from those with organic diseases. Moreover, it may be used as an additional param eter in selecting the best candidates for penile revascularization.