Prenatal protein malnutrition effects on the serotonergic system in the hippocampal formation: an immunocytochemical, ligand binding, and neurochemical study.
Prenatally protein malnourished rats born to dams maintained on a 6% casein diet during pregnancy and then fostered at birth to females on a 25% casein diet show adult alterations in hippocampal kindling and long-term potentiation and behavioral changes that all suggest dysfunction of hippocampal formation (HF). In the present investigation, compared to well-nourished controls, 220 day malnourished rats exhibited a decrease in the 5-HT fiber density in the dentate gyrus (DG) and CA3 subfield and, a 15-25% decrease 5-HT uptake sites assayed with [3H]-citalopram in CA3 and CA1. In malnourished rats, 5-HT1A receptors assayed with [3H]8-OH-DPAT were decreased by 20% in CA3. Because most hippocampal subfields showed no 5-HT changes, hippocampal 5-HT levels determined via HPLC methods were similar in adult malnourished and control rats. These results suggest that there are localized changes in the 5-HT afferent system in the hippocampal formation of the 220 day prenatally protein malnourished rat. Considering the 5-HT afferent input to inhibitory intrahippocampal neurons, the decreased 5-HT plexus may result in increased inhibition within specific hippocampal subfields despite overall normal levels of 5-HT in the total HF.
Blatt
G J
GJ
Department of Anatomy and Neurobiology, Boston University School of Medicine, MA 02118.
Chen
J C
JC
Rosene
D L
DL
Volicer
L
L
Galler
J R
JR
D017371:8-Hydroxy-2-(di-n-propylamino)tetralin; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D015283:Citalopram; D005260:Female; D005315:Fetal Diseases / Q000378:metabolism*; D006624:Hippocampus / Q000378:metabolism*; D007150:Immunohistochemistry; D008024:Ligands; D011247:Pregnancy; D011297:Prenatal Exposure Delayed Effects; D011502:Protein-Energy Malnutrition / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D011985:Receptors, Serotonin / Q000378:metabolism; D012701:Serotonin / Q000378:metabolism*
D008024:Ligands; D011985:Receptors, Serotonin; D015283:Citalopram; D012701:Serotonin; D017371:8-Hydroxy-2-(di-n-propylamino)tetralin