The sex pheromone of the male sea lamprey: First steps to understanding how it is synthesised and released

We have recently identified a potent pheromone (7alpha,12alpha,24-trihydroxy-5alpha-cholan-3-one-24-sulfate) in the male sea lamprey, Petromyzon marinus. We are now attempting, with the aid of an ELISA for this compound, to determine how and where in the body of the male lamprey this compound is synthesised and released. We have strong evidence that it is released into the water via the gills. Preliminary evidence suggests that it is synthesized in the liver. The fact that the pheromone is only released by spermiating males suggests that the synthesis is under the control of one or more testicular steroids. So far, we have found that the putative lamprey androgen, 15alphaOH-testosterone (15alpha-T) is present in females as well as males and therefore unlikely to be involved directly in the control of pheromone synthesis.