Molecular Identification and Distribution of Aquaporins in Human and Rat Testes.

Park,  Nam Cheol; Park,  Young Soo; Jung,  Jin Sup

Original Article

Korean Journal of Fertility and Sterility 2000;27(2):133-144.
Published online January 1, 2001.

Molecular Identification and Distribution of Aquaporins in Human and Rat Testes.

Nam Cheol Park, Young Soo Park, Jin Sup Jung

Abstract

OBJECTIVE
Several water channels (aquapoins; AQP) that belong to the MIP (major intrinsic protein) family have identified. In the selected tissues including red blood cells or renal tubules, water movements are abundant and/or physiologically important. Unexpectedly, a high water permeability of human and ram sperm has been reported. Recent studies showed that AQP7 and AQP8 are present in testes so that the high water permeability of human sperm suggested to be mediated by AQPs. METHOD: To identify the identity of aquaporins expressed in testes, RT-PCR was performed using degenerative primers, which were designed to correspond to highly conserved sequences surrounding the Asn-Pro-Ala (NPA) motifs in the aquaporins. New expressed AQP series were reconfirmed by immunohistochemical study using rabbit polyclonal antibodies. RESULTS: DNA sequencing of PCR products revealed that AQP2 and AQP3 mRNA as well as AQP7 and AQP8 are expressed in human and rat testes, AQP2 are expressed in spermatozoa, interstitial cells and myofibroblasts and AQP3 are expressed in myofibroblasts of semineferous tubules on immunocytochemical stain. CONCLUSION: These results indicate that multiple aquaporins are expressed in testes, and that they may have important roles in the spermatogenesis and the germ cell function of testis.