Abstract: | Factors collected from the eggs of the starfish (Pisaster giganteus) and the horsehoe crab (Limulus polyphemus) caused significant increases in the sperm cyclic nucleotide concentrations of the respective species. Sea urchin egg factors, at concentrations that resulted in maximal cyclic nucleotide elevations in sea urchin spermatozoa, had no effect on those of starfish or horseshoe crab, suggesting a species specificity with respect to egg factor-induced changes in sperm cyclic nucleotide metabolism. |