Distribution of Three Nicotinic Receptor α4 mRNA Transcripts in Rat Brain: Selective Regulation by Nicotine Administration
Article first published online: 23 NOV 2002
Journal of Neurochemistry
Volume 66, Issue 3, pages 1326–1329, March 1996
How to Cite
Yu, Z. J., Morgan, D. G. and Wecker, L. (1996), Distribution of Three Nicotinic Receptor α4 mRNA Transcripts in Rat Brain: Selective Regulation by Nicotine Administration. Journal of Neurochemistry, 66: 1326–1329. doi: 10.1046/j.1471-4159.1996.66031326.x
- Issue published online: 23 NOV 2002
- Article first published online: 23 NOV 2002
- Resubmitted manuscript received December 11, 1995; accepted December 13, 1995.
- Northern blot;
- Nicotinic receptor subunit;
- α4 gene transcripts;
- Nicotine administration
Abstract: Northern blot analysis determined whether multiple α4 transcripts for neuronal nicotinic receptors in rat brain could be detected as distinct bands. When poly(A)+ RNA was isolated from brain regions and hybridized with a Hinfl fragment of α4-1 cDNA containing a sequence shared by both α4-1 and α4-2, but little homology with other α or β subunits, bands at 6.0, 4.6, and 2.6 kb were obtained. When a Taql fragment with selectivity for α4-1 was used, a single band was present at 6.0 kb. The 6.0-kb band was least abundant in all brain regions; the 2.6-kb band was most abundant in frontal cortex, hippocampus, striatum, basal forebrain, and thalamus, whereas the 4.6-kb band was most abundant in midbrain and cerebellum. Nicotine (3.6 µmol/kg, s.c., twice daily) increased the abundance of the 4.6-kb transcript in frontal cortex significantly by 28% following 2.5 days of injections; the 6.0- and 2.6-kb transcripts were unchanged. Nicotine did not affect α4 transcripts in other brain regions. Results suggest that increased mRNA levels may mediate the nicotine-induced up-regulation of receptors in cerebral cortex.