XXII. BIOCHEMICKÝ ZJAZD - Jesseniova lekárska fakulta

Posters
7.
SECRETORY PATHWAYS SPCA1- CA2+ PUMP EXPRESSION AS ParT OF
ISCHEMIC PRECONDITIONING IN raT FOREBraIN
Martina Pavlíková, Mária Kovalská, Monika Kmeťová Sivoňová,
Zuzana Tatarková and Ján Lehotský
Department of Medical Biochemistry Jessenius Faculty of Medicine,
Comenius University, Martin, Slovakia
Neural cells of the brain have important secretory functions. They secrete many neurotransmitters
and secretory proteins. The Golgi apparatus, as part of secretory pathways
(SP), is recognized Ca2+ store, which regulates secretion by SPCA- Ca2+ATPase. In addition,
SP are involved in stress sensing and transduction of apoptotic signals. Ischemic
preconditioning (IPC) is an important phenomenon of adaptation of tissue to sub-lethal
short-term ischemia, which results in increased tolerance of tissue to the lethal ischemia.
In this study we have investigated the changes in SPCA1 expression after global
ischemic injury (IRI) in hippocampal and cortical areas. In addition, the effects of IPC on
IRI associated alternations of mRNA and protein levels of SPCA1 were determined. Rats
were preconditioned by 5 min of sub-lethal ischemia and 2 days later, 15 min of lethal
ischemia followed by reperfusion for 1h, 3h and 24h. RT-PCR and Western blot analysis
clearly detected expression of SPCA gene in injured area after IRI insult. In addition,
tissue response on the level of mRNA was maximal in the reperfusion period in both
paradigms. IPC did not change significantly the expression profile, however magnitude
of cell response was elevated. Protein level of SPCA was highest in the reperfusion time.
Our results showed that IPC affects gene expression and SPCA translation in forebrain
induced by ischemia. This suggests for a potential role of SPCA regulated secretory processes
in adaptation of neuronal circuits as response to preischemic challenge.
Acknowledgement: This work was supported by grants VEGA 0049/09, UK 10/2010,
VVCE 0064/07.
XXII. Biochemistry Congress, Martin
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