LOCALIZATION AND QUANTITY OF HYALURONAN IN UROGENITAL ORGANS OF MALE AND FEMALE RATS

The histochemical distribution of hyaluronan was analysed in Various u rogenital organs of male and female (non-pregnant and pregnant) rats b y use of a hyaluronan-binding protein and avidin biotin/peroxidase sta ining. Microwave-aided fixation was used to preserve the extracellular location of hyaluronan. The concentrations of hyaluronan in the diffe rent tissues were measured with a highly sensitive radio-assay. Hyalur onan accumulated predominantly in the connective tissue around smooth muscle fibres and in the subepithelial lamina propria. Abundant hyalur onan also occurred in perivascular and perineural connective tissue. I n the female urogenital organs, hyaluronan content was high in the vag ina and urinary bladder, and highest in the vagina during pregnancy. I n the uterus, the surface epithelium of the endometrium stained intens ely. In the ovary, the zona pellucida of the oocyte and the theca inte rna cell layer of the follicles and the follicular fluid of mature fol licles exhibited prominent staining. The corpus luteum was devoid of h yaluronan, whereas enlarged corpora lutea of pregnancy exhibited weak, patchy staining. In male urogenital organs, staining for hyaluronan w as absent from the testis and epididymis, whereas the erectile connect ive tissue of the penis stained intensely. The hyaluronan concentratio ns were high in penile tissue and urinary bladder, while testis, epidi dymis and the ductus deferens contained only little hyaluronan.