Rapid but transient increases in cholecystokinin mRNA levels in cerebral cortex following amygdaloid-kindled seizures in the rat.
Cholecystokinin-octapeptide (CCK-8S) is widely distributed in neurones of the central nervous system, where it is thought to act as a transmitter or modulator. CCK-8S has been shown to exert anti-convulsant activity in animal seizure models and changes in cortical and hippocampal CCK-immunoreactivity and preproCCK messenger RNA (mRNA) have been reported following electrically- and chemically-induced seizures. In the present study, the spatiotemporal effect of amygdaloid-kindled seizures on levels of preproCCK messenger RNA in rat brain were determined using quantitative in situ hybridization histochemistry. Stimulation-evoked seizures produced bilateral increases (45-70%) in preproCCK mRNA throughout layers II-III of the cerebral cortex. These increases were rapidly induced, occurring 30-60 min after the last stage 5 seizure, but transient, as no significant changes were detected after 2 h, or subsequently at 24 or 72 h, or 2-8 weeks, post-stimulation. Rapid changes in the relative levels of preproCCK mRNA, post-seizure, suggest a possible stabilization of preproCCK transcripts and increased production of CCK-8S peptide, which may be involved in anticonvulsant mechanisms in response to the acute seizures.
Burazin
T C
TC
University of Melbourne, Department of Medicine, Austin and Repatriation Medical Centre, Heidelberg, Victoria, Australia.
Gundlach
A L
AL
D000679:Amygdala / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000502:physiology / Q000503:physiopathology; D002540:Cerebral Cortex / Q000378:metabolism*; D002766:Cholecystokinin / Q000096:biosynthesis*; D007696:Kindling, Neurologic; D007700:Kinetics; D008297:Male; D011498:Protein Precursors / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis; D051381:Rats; D017207:Rats, Sprague-Dawley; D012640:Seizures / Q000378:metabolism / Q000503:physiopathology*; D012844:Sincalide / Q000031:analogs & derivatives / Q000096:biosynthesis; D013997:Time Factors; D014158:Transcription, Genetic
C090019:8-sulfocholecystokinin octapeptide; D011498:Protein Precursors; D012333:RNA, Messenger; C042082:preprocholecystokinin; D002766:Cholecystokinin; D012844:Sincalide