New ionic targets of 3,3′,5′-triiodothyronine at the plasma membrane of rat Sertoli cells

Publication date: Available online 9 January 2019Source: Biochimica et Biophysica Acta (BBA) - BiomembranesAuthor(s): Ana Paula Zanatta, Renata Gonçalves, Leila Zanatta, Geisel Túlio de Oliveria, Ana Luiza Ludwig Moraes, Ariane Zamoner, Víctor Fernández-Dueñas, Débora Lanznaster, Francisco Ciruela, Carla Inês Tasca, Christelle Delalande, Danusa Menegaz, Fátima Regina Mena Barreto SilvaAbstractThe functions of Sertoli cells, which structurally and functionally support ongoing spermatogenesis, are effectively modulated by thyroid hormones, amongst other molecules. We investigated the mechanism of action of rT3 on calcium (45Ca2+) uptake in Sertoli cells by means of in vitro acute incubation. In addition, we performed electrophysiological recordings of potassium efflux in order to understand the cell repolarization, coupled to the calcium uptake triggered by rT3. Our results indicate that rT3 induces nongenomic responses, as a rapid activation of whole-cell potassium currents in response to rT3 occurred in <5 min in Sertoli cells. In addition, the rT3 metabolite, T2, also exerted a rapid effect on calcium uptake in immature rat testis and in Sertoli cells. rT3 also modulated calcium uptake, which occurred within seconds via the action of selective ionic channels and the Na+/K+ ATPase pump. The rapid response of rT3 is essentially triggered by calcium uptake and cell repolarization, which appear to mediate the secretory functions of Sertoli cells.Graphical abstract
Source: Biochimica et Biophysica Acta (BBA) Biomembranes - Category: Biochemistry Source Type: research