A. Taranta et al., OMEGA-CONOTOXIN-SENSITIVE CA2-GATED CHANNELS MODULATE PROTEIN SECRETION IN CULTURED RAT SERTOLI CELLS( VOLTAGE), Molecular and cellular endocrinology, 126(2), 1997, pp. 117-123
Recent results have demonstrated that substantial calcium influx in ra
t Sertoli cells is mediated by cation channels of both Land N-type. In
this report we have investigated the possible role of such channels i
n the protein secretion of immature rat Sertoli cell monolayers. The b
locking of N-type voltage-gated channels by omega-conotoxin (omega-CTX
) GVIA results in a 50-60% inhibition of the protein secretion in the
culture medium while total protein and RNA synthesis are not affected.
The same extent of protein secretion inhibition is obtained in FSH-st
imulated Sertoli cells. L-type voltage-gated channels apparently are n
ot involved in such a modulation. These data, showing that a major fra
ction of secreted proteins from cultured rat Sertoli cells is Ca2+ dep
endent, represent the first evidence of a physiological role of voltag
e-operated Ca2+ channels in mammalian testis. (C) 1997 Elsevier Scienc
e Ireland Ltd.