Starfish gonad: action and chemical identification of spawning inhibitor.

The gamete-shedding substance obtained from the radial nerves induces spawning when it is applied to the gonads of mature starfish in vivo and in vitro. A substance that inhibits the action of this spawning factor is present in both ovary and testis; it has been isolated from testis of Asterina pectinifera and chemically identified as L-glutamic acid.