Regulation of the motility of fowl spermatozoa by calcium and cAMP

Abstract
Using an objective light-scattering technique, it was confirmed that washed fowl spermatozoa become immotile as the temperature is raised from 30.degree. C to the normal body temperature of 40-41.degree. C. Motility of washed spermatozoa was restored at 40.degree. C by the addition of caffeine or calcium, both stimulating motility to a maximum in a dose-dependent manner. Neither effector stimulated the motility of spermatozoa at 30.degree. C. Caffeine, but not calcium, caused an increase in sperm cAMP levels at 40.degree. C. The concentrations of calcium and cAMP in untreated spermatozoa were not significantly different in samples incubated at 30.degree. C or 40.degree. C.