Lack of relationship between cyclic nucleotide levels and spermatozoal function in human semen

Cyclic adenosine 3':5'-monophosphate (cyclic AMP) levels were determined in 103 samples of human semen and grouped according to the number of spermatozoa in the ejaculate. No correlation was found between cyclic AMP concentrations and the number, motility, and morphology of the spermatozoa or the fructose content, pH, and volume of the ejaculate. Similar findings were obtained with cyclic guanosine 3':5'-monophosphate levels in 24 samples of human semen. Therefore, cyclic nucleotide levels in human semen appear to be derived from sources other than spermatozoal adenylyl or guanylyl cyclase.