Effects of purinergic agonists on aromatase and gamma-glutamyl transpeptidase activities and on transferrin secretion in cultured Sertoli cells

Abstract

To study the role of extracellular nucleosides and nucleotides in the regulation of Sertoli cells, the effects of agonists which occupy A 1 and P 2 purinergic receptors on aromatase and gamma-glutamyl transpeptidase ( -GTP) activities and on transferrin secretion were tested. Sertoli cell treatment with purinergic agonists for a prolonged period of time (72 h) resulted in an increase in aromatase activity under basal conditions. In cultures stimulated with FSH, purinergic agonists counteracted the inhibitory effect on aromatase activity that long-term treatment with FSH promoted. The effects of prolonged treatments with purinergic agonists on the other two parameters of Sertoli cell function were less pronounced. Neither -GTP activity nor transferrin secretion was modified under basal conditions. On the other hand, under conditions where cell differentiation was favored by FSH treatment, reductions in -GTP activity and transferrin secretion were usually observed. The results obtained in dbcAMPstimulated cultures suggested that A 1 agonists exert their regulatory function at the level of cAMP formation while P 2 agonists act at a more distal point. The fact that morphological changes induced by FSH were reversed by both types of agonists, while those induced by dbcAMP were only abrogated by P 2 agonists, supports this hypothesis. In summary, these results demonstrate that purinergic agonists may be important in the regulation of Sertoli cell function.

Purinergic signalling in the reproductive system in health and disease

“…ATP depolarises and produces an increase in [Ca 2+ ] i from intracellular stores in rat Sertoli cells, consistent with P2Y receptor activation, but it also induces a selective Na + influx from the extracellular medium consistent with activation of P2X receptors [126]. Prolonged treatment of cultured Sertoli cells with purinergic agonists for A 1 and P2 receptors led to an increase in aromatase, γ-glutamyl transpeptidase activities and transferrin secretion [271]. Oestradiol secretion in rat Sertoli cells was produced by extracellular ATP via both P2X and P2Y receptors, which led to increases in both [Ca 2+ ] i and [Na + ] i and membrane depolarisation [351].…”

Ectonucleotidase activities in Sertoli cells from immature rats

“…Several reports have demonstrated the presence of adenosine receptors in Sertoli cells (10,11) and their modulation by adenosine and different adenosine analogues (4,8,9). The purinoreceptor subtype P 2Y2 is present in these cells (5) and its modulation by ATP has been well demonstrated (5)(6)(7). In Sertoli cells, extracellular ATP and adenosine can modulate the hormonal response to FSH, decreasing cAMP levels (4,5,(8)(9)(10), and can regulate anionic (6) and transferrin secretion (7) and the intracellular levels of Ca 2+ by inositol phospholipid turnover (5).…”

“…Previous studies have demonstrated that adenosine nucleotides can modulate Sertoli cell responses through the purinoreceptors present on these cells (4)(5)(6)(7)(8)(9)(10).…”

Molecular mechanisms involved in Sertoli cell adaptation to glucose deprivation

“…Animals were killed by asphyxiation with CO2 and decapitated. Testes were removed and decapsulated, and Sertoli cell isolation was performed as described previously (26). Briefly, decapsulated testes were digested with 0.1% collagenase and 0.006% soybean trypsin inhibitor in Hanks' balanced salt solution for 5 min at room temperature.…”