Acute slices of mice testis seminiferous tubules unveil spontaneous and synchronous Ca2+ oscillations in germ cell clusters.
Spermatogenic cell differentiation involves changes in the concentration of cytoplasmic Ca(2+) ([Ca(2+)]i); however, very few studies exist on [Ca(2+)]i dynamics in these cells. Other tissues display Ca(2+) oscillations involving multicellular functional arrangements. These phenomena have been studied in acute slice preparations that preserve tissue architecture and intercellular communications. Here we report the implementation of intracellular Ca(2+) imaging in a sliced seminiferous tubule (SST) preparation to visualize [Ca(2+)]i changes of living germ cells in situ within the SST preparation. Ca(2+) imaging revealed that a subpopulation of male germ cells display spontaneous [Ca(2+)]i fluctuations resulting from Ca(2+) entry possibly throughout Ca(V)3 channels. These [Ca(2+)]i fluctuation patterns are also present in single acutely dissociated germ cells, but they differ from those recorded from germ cells in the SST preparation. Often, spontaneous Ca(2+) fluctuations of spermatogenic cells in the SST occur synchronously, so that clusters of cells can display Ca(2+) oscillations for at least 10 min. Synchronous Ca(2+) oscillations could be mediated by intercellular communication via gap junctions, although intercellular bridges could also be involved. We also observed an increase in [Ca(2+)]i after testosterone application, suggesting the presence of functional Sertoli cells in the SST. In summary, we believe that the SST preparation is suitable to explore the physiology of spermatogenic cells in their natural environment, within the seminiferous tubules, in particular Ca(2+) signaling phenomena, functional cell-cell communication, and multicellular functional arrangements.
Departamento de Genética del Desarrollo y Fisiología Molecular, Instituto de Biotecnología, Universidad Nacional Autónoma de México, Cuernavaca, Morelos, México.
Claudia
C
Sánchez-Cárdenas
Adán
A
Guerrero
Claudia Lydia
CL
Treviño
Arturo
A
Hernández-Cruz
Alberto
A
Darszon
D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology; D020747:Calcium Channels, T-Type / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects / Q000502:physiology*; D002470:Cell Survival; D005854:Germ Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D051379:Mice; D008867:Microtomy / Q000379:methods*; D008954:Models, Biological; D012671:Seminiferous Tubules / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D012708:Sertoli Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D013048:Specimen Handling / Q000379:methods; D013091:Spermatogenesis / Q000502:physiology; D013737:Testis / Q000166:cytology* / Q000187:drug effects
C498197:Cacna1g protein, mouse; D002121:Calcium Channel Blockers; D020747:Calcium Channels, T-Type