Effect of a diet-induced n-3 PUFA depletion on cholinergic parameters in the rat hippocampus.
Because brain membranes contain large amounts of docosahexaenoic acid (DHA, 22:6n-3), and as (n-3) PUFA dietary deficiency can lead to impaired attention, learning, and memory performance in rodents, we have examined the influence of an (n-3) PUFA-deprived diet on the central cholinergic neurotransmission system. We have focused on several cholinergic neurochemical parameters in the frontal cortex and hippocampus of rats fed an (n-3) PUFA-deficient diet, compared with rats fed a control diet. The (n-3) PUFA deficiency resulted in changes in the membrane phospholipid compositions of both brain regions, with a dramatic loss (62-77%) of DHA. However, the cholinergic pathway was only modified in the hippocampus and not in the frontal cortex. The basal acetylcholine (ACh) release in the hippocampus of deficient rats was significantly (72%) higher than in controls, whereas the KCl-induced release was lower (34%). The (n-3) PUFA deprivation also caused a 10% reduction in muscarinic receptor binding. In contrast, acetylcholinesterase activity and the vesicular ACh transporter in both brain regions were unchanged. Thus, we evidenced that an (n-3) PUFA-deficient diet can affect cholinergic neurotransmission, probably via changes in the phospholipid PUFA composition.
Aïd
Sabah
S
INRA, Laboratoire de Nutrition et Sécurité Alimentaire, Jouy-en-Josas, France.
Vancassel
Sylvie
S
Poumès-Ballihaut
Carine
C
Chalon
Sylvie
S
Guesnet
Philippe
P
Lavialle
Monique
M
D000109:Acetylcholine / Q000378:metabolism; D000110:Acetylcholinesterase / Q000378:metabolism; D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D004032:Diet; D005231:Fatty Acids, Unsaturated / Q000172:deficiency*; D005260:Female; D005625:Frontal Lobe / Q000737:chemistry / Q000502:physiology; D006624:Hippocampus / Q000737:chemistry / Q000502:physiology*; D026901:Membrane Transport Proteins; D010743:Phospholipids / Q000032:analysis / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D011976:Receptors, Muscarinic / Q000378:metabolism; D009435:Synaptic Transmission; D050494:Vesicular Acetylcholine Transport Proteins; D033921:Vesicular Transport Proteins
D002352:Carrier Proteins; D005231:Fatty Acids, Unsaturated; D026901:Membrane Transport Proteins; D010743:Phospholipids; D011976:Receptors, Muscarinic; C493461:Slc18a3 protein, rat; D050494:Vesicular Acetylcholine Transport Proteins; D033921:Vesicular Transport Proteins; D000110:Acetylcholinesterase; D000109:Acetylcholine