Hydrolytic enzymes in the coelomic cells of the polychaeteNereis virens during sexual maturation

Abstract

Nereis virens were collected between April 1989 and April 1990 at Yerseke, Oosterscheldt Bay, The Netherlands. Activities of the hydrolytic enzymes arylsulfatase, acid phosphatase, N-acetylglucosaminidase, aminopeptidase, and carboxylesterase were investigated in coelomic cells (elaeocytes) of individuals at different stages of maturation as determined by the time course of oocyte growth. On a protein-content basis, up to ten-fold higher specific activities were present in the elaeocytes compared to the body-wall tissue. Acid phosphatase, N-acetylglucosaminidase, leucine aminopeptidase, and long- and medium-chain esterase increased continuously from the beginning to the later stage of sexual maturation, with a decline in prespawning individuals. Shortchain esterase and acid aminopeptidase did not show corresponding changes. Activities at different maturation stages were similar for males and females, with the exception of arylsulfatase activity, which was sex-specific and almost lacking in male elaeocytes. The high hydrolytic activities present in the elaeocytes as well as the increase in these activities during sexual maturation are in agreement with the function of these cells in phagocytizing muscle fragments (sarcolytes), which arise as a result of drastic histolysis of the body musculature ofN. virens during the process of sexual maturation.