Status epilepticus induced by pilocarpine and Ca2+ transport by microsome in the hippocampus of rats.
An increase in intra-neuronal Ca(2+) concentration has been associated to status epilepticus (SE). Ca(2+) is stored in the endoplasmic reticulum, mediated by the Ca(2+)-ATPases (SERCAs). Here we studied the Ca(2+)-ATPase activity and the SERCA2b distribution in the hippocampus of rats submitted to 5h of SE. The Ca(2+)-uptake was measured using [45Ca]CaCl(2) and the hippocampal distribution of SERCA2b was analyzed by immunohistochemistry. A reduction in the amount of cells expressing SERCA2b in CA1, CA3 and dentate gyrus was observed. However, the surviving cells of these regions increased the SERCA2b immunoreactivity, when compared with control tissues. The Ca(2+)-ATPase activity measured in all hippocampal formation was not modified by SE. These results suggest that SE promotes a redistribution of SERCA2b in the hippocampus as a compensatory Ca(2+)-transport mechanism.
Costa
Maricilia S
MS
Disciplina de Neurologia Experimental, UNIFESP-EPM, São Paulo, Brazil. mscosta@univap.br
Funke
Marcelo G
MG
de Meis
Leopoldo
L
Cavalheiro
Esper A
EA
Naffah-Mazzacoratti
Maria da Graça
Mda G
D000255:Adenosine Triphosphate / Q000378:metabolism; D000704:Analysis of Variance; D000818:Animals; D001692:Biological Transport / Q000502:physiology; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D000252:Calcium-Transporting ATPases / Q000378:metabolism; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D006624:Hippocampus / Q000378:metabolism*; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008861:Microsomes / Q000378:metabolism*; D006899:Mixed Function Oxygenases; D010862:Pilocarpine; D051381:Rats; D017208:Rats, Wistar; D013226:Status Epilepticus / Q000139:chemically induced / Q000378:metabolism*; D013997:Time Factors
D010862:Pilocarpine; D000255:Adenosine Triphosphate; D006899:Mixed Function Oxygenases; D000252:Calcium-Transporting ATPases; D002118:Calcium