Further evidence for cholinergic habenulo-interpeduncular neurons: pharmacologic and functional characteristics.
Placement of high frequency lesions in the medial habenular area results in a large depletion of acetylcholine (ACh) levels, choline acetyltransferase (ChAc) activity, and high affinity choline uptake in the interpeduncular nucleus area (IPN) at 1, 3 and 7 days post-lesion. Areas adjacent to the IPN did not have a reduction in ChAc activity. The reduction in high affinity choline uptake was selective in that there was no change in the uptake of L-[3H]tyrosine or L-[3H]glutamic acid. Unlike the cholinergic septal-hippocampal neurons, there was no rise in ACh levels in the IPN 1 h after placement of lesion, or 30 min after administration of pentobarbital. While the IPN probably has a much denser cholinergic innervation than the hippocampus (as evidenced by much higher ACh levels, ChAc activity and choline uptake levels), it has only one-fourth as many [3H]QNB binding sites (a measure of cholinergic muscarinic receptors). This, some of the habenulo-interpeduncular neurons are probably cholinergic, and they may have pharmacologic and functional differences compared to the septal-hippocampal neurons.
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D001561:Benzilates / Q000378:metabolism; D002794:Choline / Q000378:metabolism; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D005971:Glutamates / Q000378:metabolism; D008297:Male; D008636:Mesencephalon / Q000201:enzymology / Q000378:metabolism* / Q000648:ultrastructure; D009434:Neural Pathways; D011812:Quinuclidines / Q000378:metabolism; D051381:Rats; D013574:Synaptosomes / Q000378:metabolism; D013788:Thalamus / Q000378:metabolism*; D014443:Tyrosine / Q000378:metabolism
D001561:Benzilates; D005971:Glutamates; D011812:Quinuclidines; D014443:Tyrosine; D002795:Choline O-Acetyltransferase; D002794:Choline; D000109:Acetylcholine