EFFECT OF MESENCHYMAL GLANDULAR INDUCTORS ON THE GROWTH AND CYTODIFFERENTIATION OF NEONATAL MOUSE SEMINAL-VESICLE EPITHELIUM

To investigate the developmental properties of glandular mesenchymal i nductors along the cranial-caudal extent of the developing male urogen ital tract, neonatal mouse seminal vesicle epithelium (SVE) was combin ed with mesenchyme of the seminal vesicle (SVM), urogenital sinus (UGM ), bulbourethral gland (BUG-M), or bladder (BLM) and grafted under the renal capsule of adult syngeneic or athymic male mice. Both SVM + SVE and UGM + SVE tissue recombinants expressed SV histogenesis and SV se cretory proteins. BUG-M + SVE recombinants exhibited extensive growth as evidenced by a 36-fold increase in wet weight and a 27-fold increas e in DNA content; however, the glandular structures that were induced in the SVE lacked the convoluted mucosa typical of SV. Furthermore, ne ither SV nor prostatic secretory proteins were detected in these recom binants. SVE grown in association with BLM failed to develop altogethe r. Thus, the ability to promote SV histogenesis and function is distin ctly different in mesenchyme of cranial (SVM and UGM) versus caudal (B UG-M) regions. This implies the existence of a glandular inductive fie ld in the developing male urogenital tract within which inductive acti vity varies regionally.