Glucose and lactate regulate maitotoxin-activated Ca2+ entry in spermatogenic cells: the role of intracellular [Ca2+].
Maitotoxin (MTX), a potent polyether marine biotoxin, induces Ca(2+) entry in different mammalian cells by activation of Ca(2+) channels. The identity and modulation of the MTX-activated Ca(2+) entry pathway is not known. In this work, we show, for the first time, that glucose and lactate can modulate the excitability of spermatogenic cell MTX-activated Ca(2+) channels. Physiological and pharmacological evidences indicate that glucose and lactate differentially affect MTX-activated Ca(2+) entry mainly through changes that these substrates induce on intracellular Ca(2+) stores and the concentration of intracellular Ca(2+) ([Ca(2+)](i)) in spermatogenic cells. Our findings strongly suggest that MTX-activated Ca(2+) channels in spermatogenic cells can be regulated by a Ca(2+)-CaM-dependent protein kinase.
Reyes
Juan G
JG
Instituto de Quimica, Pontificia Universidad Catolica de Valparaiso, Valparaiso, Chile. jreyes@ucv.cl
Osses
Nelson
N
Knox
Marcela
M
Darszon
Alberto
A
Treviño
Claudia L
CL
D000818:Animals; D002118:Calcium / Q000494:pharmacology / Q000502:physiology*; D003593:Cytoplasm / Q000378:metabolism; D005854:Germ Cells / Q000378:metabolism; D005947:Glucose; D007477:Ions / Q000378:metabolism; D019344:Lactic Acid; D008297:Male; D008387:Marine Toxins; D035964:Oxocins; D051381:Rats; D017207:Rats, Sprague-Dawley; D000095702:Polyether Toxins
D002118:Calcium; D005947:Glucose; D007477:Ions; D019344:Lactic Acid; D008387:Marine Toxins; D035964:Oxocins; C020394:maitotoxin; D000095702:Polyether Toxins