Germ cell-Sertoli cell interactions: the effect of testicular maturation on the synthesis of cyclic protein-2 by rat Sertoli cells.
Cyclic Protein-2 (CP-2) is synthesized in a stage-specific manner by mature rat Sertoli cells within stage VI and VII seminiferous tubules. To determine how testicular maturation affects CP-2 synthesis, we cultured 20 cm of tubules encompassing all stages of the cycle from rats 17, 35, 45, and 75 days old. The greatest increase in CP-2 synthesis was found to occur between 35 and 45 days and exceeded that observed for transferrin and sulfated glycoprotein (SGP)-2. Additionally, two-dimensional gel analysis indicated that secretion of CP-2 increased from 35 to 45 days to a greater extent than the secretion of SGP-1 and SGP-2 and transferrin. Biochemical analysis also demonstrated that CP-2 synthesis was stage-specific by 45 days. Immunocytochemistry expanded these observations; CP-2 was not detected in 7-35-day-old Sertoli cells. However, at 36 days, CP-2 was detected in Sertoli cells in stage VI and VII tubules but not at any other stage. CP-2 concentration in stage VI-VII tubules was increased by 38 days, but was unchanged thereafter. Finally, we immunocytochemically examined age-related changes in CP-2 concentration of the proximal convoluted kidney tubule. This analysis revealed that, at 1 wk, CP-2 was present in all proximal tubules except those in the subcapsular area; however, by 14 days, CP-2 was detected in all proximal tubules. This comparison of Sertoli cells and proximal tubule cells indicates that CP-2 content is determined by the maturity of a cell and not by the age of the animal.
Zabludoff
S D
SD
Department of Population Dynamics, Johns Hopkins University School of Hygiene and Public Health, Baltimore, Maryland 21205.
Karzai
A W
AW
Wright
W W
WW
D000818:Animals; D051152:Clusterin; D015180:Electrophoresis, Gel, Two-Dimensional; D006023:Glycoproteins / Q000096:biosynthesis / Q000378:metabolism; D007150:Immunohistochemistry; D007668:Kidney / Q000166:cytology / Q000378:metabolism; D008297:Male; D018832:Molecular Chaperones; D011506:Proteins / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D012671:Seminiferous Tubules / Q000378:metabolism; D012708:Sertoli Cells / Q000378:metabolism*; D013091:Spermatogenesis; D013737:Testis / Q000166:cytology / Q000254:growth & development*; D014168:Transferrin / Q000096:biosynthesis
D051152:Clusterin; D006023:Glycoproteins; D018832:Molecular Chaperones; D011506:Proteins; D014168:Transferrin