[17 beta-estradiol inhibits T-type calcium channels in mouse spermatogenic cells].
OBJECTIVE
To investigate the effect of 17 beta-estradiol (E2) on T-type calcium currents (ICaT) in spermatogenic cells.


METHODS
Ca2+ currents were obtained in acutely dissociated mouse spermatogenic cells by the whole-cell patch clamp technique and the effects of E2 on ICaT were observed.


RESULTS
E2 at the concentrations of 1, 10 and 100 micromol/L significantly inhibited ICaT in the mouse spermatogenic cells, with the KC50 value of 8.89 micromol/L and the inhibition rates of (13.48 +/- 1.86) %, (28.98 +/- 2.70) and (52.93 +/- 3.42)%, respectively (n = 6, P < 0.05). E2 of 100 micromol/L significantly changed the activation and inactivation of ICaT: the half activation potential (Va 1/2) and the activation steepness factor (Ka) from ( -48.94 +/- 0.22) mV and (5.19 +/- 0.19) mV to (-54.34 +/- 1.02) mV and (6.02 +/- 0.84) mV ( n = 5, P < 0.05) , and the half inactivation potential (Vi 1/2) and the inactivation steepness factor (Ki) from (-56.51 +/- 0.13) mV and (3.36 +/- 0.11) mV to (-61.78 +/- 0.50) mV and (4.25 +/- 0.37) mV, respectively (n = 5, P < 0.05).


CONCLUSIONS
E2 has a significant inhibitory effect on ICaT in mouse spermatogenic cells in a con-centration-dependent manner.
Lu
Liang
L
The Ministry of Education Key Lab of Modern Toxicology, Nanjing Medical University, Nanjing, Jiangsu 210029, China.
Wang
Chang-song
CS
Gao
Xiao-hua
XH
Wang
Jun
J
Cheng
Jie
J
Gao
Rong
R
Xiao
Hang
H
D000818:Animals; D020747:Calcium Channels, T-Type / Q000502:physiology*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000494:pharmacology*; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D018408:Patch-Clamp Techniques; D013087:Spermatids / Q000166:cytology / Q000187:drug effects* / Q000502:physiology
D020747:Calcium Channels, T-Type; D004958:Estradiol