Prenatal nicotine exposure: effects on locomotor activity and central [125I]alpha-BT binding in rats.
Maternal smoking during pregnancy or in utero exposure of the fetus to nicotine may result in learning difficulties and hyperactivity in the child. To elucidate possible involvement of the alpha(7) nicotinic receptor subtype in these behavioral impairments, pregnant dams were treated with nicotine (9 mg/kg/day) via osmotic minipumps throughout gestation. Male offspring were weaned at postnatal day 18, and were tested for locomotor activity at postnatal days 20-24. Pups were sacrificed on postnatal day 36-38 and 18 discrete brain areas were analyzed for [125I]alpha-bungarotoxin (alpha-BT) binding by quantitative autoradiography. Prenatal nicotine caused an elevation in locomotor activity (vertical movements) in offspring. [125I]alpha-BT binding was significantly reduced in the hippocampal CA1 region (29%), dentate gyrus (22%), and medial geniculate nucleus (29%). These findings suggest that some of the behavioral abnormalities induced by prenatal nicotine exposure may be due to a reduction of alpha(7) nicotinic receptors in discrete brain regions.
Tizabi
Y
Y
Department of Pharmacology, College of Medicine, Howard University, Washington, DC 20059, USA.
Russell
L T
LT
Nespor
S M
SM
Perry
D C
DC
Grunberg
N E
NE
D000818:Animals; D001665:Binding Sites / Q000187:drug effects; D002038:Bungarotoxins / Q000378:metabolism*; D005260:Female; D005731:Ganglionic Stimulants / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D007457:Iodine Radioisotopes; D009043:Motor Activity / Q000187:drug effects*; D009538:Nicotine / Q000494:pharmacology*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011297:Prenatal Exposure Delayed Effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D011978:Receptors, Nicotinic / Q000378:metabolism; D064569:alpha7 Nicotinic Acetylcholine Receptor
D002038:Bungarotoxins; C579165:Chrna7 protein, rat; D005731:Ganglionic Stimulants; D007457:Iodine Radioisotopes; D011978:Receptors, Nicotinic; D064569:alpha7 Nicotinic Acetylcholine Receptor; D009538:Nicotine