Detection of mRNA transcripts of cyclic nucleotide phosphodiesterase subtypes in ejaculated human spermatozoa

Multiple types and subtypes, including splice variants, of cyclic nucleotide phosphodiesterases (PDE) have been shown to be expressed in various tissues and organs. They control the intracellular level of cyclic nucleotides and are involved in hormonal signalling. In human spermatozoa, PDE play an important role in the regulation of motility, capacitation and acrosome reaction. The aim of this study was to investigate which transcripts of the different PDE types and subtypes could be found in human spermatozoa using reverse transcription-polymerase chain reaction (RT-PCR). Ejaculated spermatozoa from 10 single semen samples as well as another three semen sample pools were separated by swim-up and were investigated by RT-PCR. We obtained PCR products of the PDE types/subtypes 1A/B/C, 2, 3A/B, 4A/B/C, 5, and 8 with different intensities. Control PCR for leukocyte contamination were negative and contamination by other somatic cells was excluded by the spermatozoa preparation protocol, immunohistochemistry and visual examination. These results demonstrated for the first time that human ejaculated spermatozoa contain an extended pattern of PDE mRNA transcripts.