Prostaglandin and prostaglandin synthetase in the cricket, Acheta domesticus

Prostaglandin (PG) synthetase was present in the testes, seminal vesicles, and spermatophores of the male house cricket, Acheta domesticus. The enzyme was not detected in bursa copulatrix, spermatheca, spermathecal canal, and oviducts from virgin females, while substantial activity was measured in the same tissue from mated females. The female appears to receive the enzyme from the spermatophore. A PGE₂-like material was detected by radioimmunoassay in A. domesticus testes and to a lesser extent in the remainder of the male reproductive tract. PG went undetected in virgin female reproductive tissues, while the same tissues from mated females contained an average of 589 pg of PGE₂-like material per female. In in vivo studies, injected PGE₁, PGE₂, and to a smaller degree PGF_2α stimulated oviposition by virgin females. Moreover, N-acetyl-p-aminophenol, a PG synthetase inhibitor, suppressed oviposition in mated females. Post-copulatory PG biosynthesis in the female reproductive tract might be partially responsible for triggering oviposition in A. domesticus. Since PG synthetase appears to be acquired from the male, it could be considered a primer pheromone.