Effect of 1¦Á,25-dihydroxyvitamin D₃ in plasma membrane targets in immature rat testis: Ionic channels and gamma-glutamyl transpeptidase activity

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• 作者：Leila Zanatta^a ;   ; ^b ; Ariane Zamoner^a ; Renata Gonç ; alves^a ; Ana Paula Zanatta^a ; Hé ; lè ; ne Bouraï ; ma-Lelong^b ; Camille Bois^b ; Serge Carreau^b ; Fá ; tima Regina Mena Barreto Silva^a ;   ; ^{mena@mbox1.ufsc.br}
• 关键词：1¦Á ; 25(OH)₂-vitamin D₃ ; Calcium uptake ; Gamma-glutamyl transpeptidase ; PKA ; PKC ; ERK
• 刊名：Archives of Biochemistry and Biophysics
• 出版年：2011
• 出版时间：November 2011
• 年：2011
• 卷：515
• 期：1-2
• 页码：46-53
• 全文大小：1102 K

文摘

1¦Á,25-Dihydroxyvitamin D₃ (1,25D₃) is critical for the maintenance of normal reproduction since reduced fertility is observed in vitamin D-deficient male rats. The aim of this study was to investigate the effect of 1,25D₃ in 30-day-old rat testicular plasma membrane targets (calcium uptake and gamma-glutamyl transpeptidase (GGTP) activity), as well as to highlight the role of protein kinases in the mechanism of action of 1,25D₃. The results demonstrated that 1,25D₃ induced a fast increase in calcium uptake in rat testis through a nongenomic mechanism of action. This effect was dependent on PKA, PKC and MEK. Moreover, ionic channels, such as ATP- and Ca²⁺-dependent K⁺ channels and Ca²⁺-dependent Cl^{?/sup> channels, are involved in the mechanism of action. The use of BAPTA-AM showed that [Ca2+]_i was also implicated, and the incubation with digoxin produced an increase in 45Ca2+ uptake indicating that the effect of 1,25D₃ may also result from Na+/K+-ATPase inhibition. In addition, 1,25D₃ was able to increase the GGTP activity. Considered together, our results indicate a PKA/PKC/MEK-dependent 1,25D₃ pathway as well as ionic involvement leading to 45Ca2+ uptake in immature rat testis. These findings demonstrate that 1,25D₃ stimulates calcium uptake and increases GGTP activity which may be involved in male reproductive functions.}