title: Differential effects of acute and chronic electroconvulsive shock on the abundance of messenger RNAs for voltage-dependent potassium channel subunits in the rat brain.
abstract: The effect of acute and chronic electroconvulsive shock on the abundance of messenger RNAs encoding voltage-dependent potassium channel subunits in the rat brain was determined by in situ hybridization histochemistry with [35S]dATP-labelled oligonucleotides at 6 h, 24 h and three weeks following the last shock. The messenger RNA abundance of two voltage-dependent potassium channel subunits, Kv1.2 and Kv4.2, was altered by electroconvulsive shock but in different ways. In acute electroconvulsive shock experiments, Kv1.2 and Kv4.2 messenger RNA abundance in the dentate gyrus were reduced 6 h following the shock and returned to control levels after 24 h. In chronic electroconvulsive shock-treated rats, Kv1.2 messenger RNA abundance showed similar changes to those in acute electroconvulsive shock: it was reduced 6 h after the last shock and had recovered after 24 h. Kv4.2 messenger RNA abundance in chronic electroconvulsive shock-treated rats, however, showed adaptive changes: 6 h after the last shock there were no changes in its abundance while 24 h after the last shock there was a significant increase in the dentate gyrus. The changes in Kv1.2 and Kv4.2 messenger RNA abundance following electroconvulsive shock were only observed in the dentate gyrus and not in cornu ammonis 1 and cornu ammonis 3 of hippocampus or frontal-parietal cortex. Two other potassium channel subunits, Kv1.1 and Kv1.4, were not affected by either acute or chronic electroconvulsive shock. These findings indicate that acute and chronic electroconvulsive shock affect the gene expression of voltage-dependent potassium channel subunits with specificities for channel type, anatomical region and timing.
authors.affiliation: Oxford University SmithKline Beecham Centre for Applied Neuropsychobiology, University Department of Clinical Pharmacology, Radcliffe Infirmary, U.K.
authors.forename: Q
authors.initials: Q
authors.lastname: Pei
authors.forename: P W
authors.initials: PW
authors.lastname: Burnet
authors.forename: D G
authors.initials: DG
authors.lastname: Grahame-Smith
authors.forename: T S
authors.initials: TS
authors.lastname: Zetterström
mesh_terms: D000818:Animals; D001345:Autoradiography; D001483:Base Sequence; D001923:Brain Chemistry / Q000502:physiology*; D018891:Dentate Gyrus / Q000166:cytology / Q000187:drug effects / Q000502:physiology; D004594:Electrophysiology; D004597:Electroshock; D017403:In Situ Hybridization; D008297:Male; D051379:Mice; D008818:Mice, Neurologic Mutants; D008969:Molecular Sequence Data; D015221:Potassium Channels / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
chemical_list: D015221:Potassium Channels; D012333:RNA, Messenger