Analysis of Ca(2+) currents in spermatocytes from mice lacking Ca(v)2.3 (alpha(1E)) Ca(2+) channel.
In mammalian male germ-line cells, low-voltage-activated (LVA) Ca(2+) current has been identified and its electrophysiological properties have been studied. To investigate whether alpha(1)2.3 (alpha(1E)) subunit of the voltage-dependent Ca(2+) channel codes for the LVA current, whole-cell patch clamp and following reverse transcription-polymerase chain reaction (RT-PCR) experiments were performed in pachytene spermatocytes from Ca(v)2.3+/+ and Ca(v)2.3-/- mice. Whole-cell current in acutely dissociated pachytene spermatocytes from Ca(v)2.3+/+ and Ca(v)2.3-/- mice displayed a typical profile of LVA Ca(2+) currents and kinetics with no significant differences. Single-cell RT-PCR revealed the expression of Cacna1g in the pachytene spermatocytes from Ca(v)2.3+/+ and Ca(v)2.3-/- mice in which LVA Ca(2+) currents were actually recorded. These results suggest that the Ca(v)2.3 channel makes no detectable contribution to the LVA Ca(2+) current in the pachytene spermatocyte. Instead, Ca(v)3 family such as Ca(v)3.1 may be the likely candidates responsible for the LVA currents in pachytene spermatocytes.
Sakata
Y
Y
Department of Pharmacology, Graduate School of Medicine, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo-ku, Tokyo, 113-8519, Japan.
Saegusa
H
H
Zong
S
S
Osanai
M
M
Murakoshi
T
T
Shimizu
Y
Y
Noda
T
T
Aso
T
T
Tanabe
T
T
D000818:Animals; D001483:Base Sequence; D002118:Calcium / Q000378:metabolism*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D015220:Calcium Channels / Q000172:deficiency* / Q000235:genetics / Q000378:metabolism; D020908:Calcium Channels, R-Type; D020747:Calcium Channels, T-Type / Q000235:genetics / Q000378:metabolism; D027682:Cation Transport Proteins; D017353:Gene Deletion; D007700:Kinetics; D008297:Male; D008540:Meiosis; D051379:Mice; D008969:Molecular Sequence Data; D018408:Patch-Clamp Techniques; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013090:Spermatocytes / Q000166:cytology / Q000378:metabolism*; D020866:omega-Conotoxin GVIA / Q000494:pharmacology
C498916:Cacna1e protein, mouse; C498197:Cacna1g protein, mouse; D002121:Calcium Channel Blockers; D015220:Calcium Channels; D020908:Calcium Channels, R-Type; D020747:Calcium Channels, T-Type; D027682:Cation Transport Proteins; D012333:RNA, Messenger; D020866:omega-Conotoxin GVIA; D002118:Calcium