Premium
Comparative ontogenic profile of cholinergic markers, including nicotinic and muscarinic receptors, in the rat brain
Author(s) -
Aubert Isabelle,
Cécyre Danielle,
Gauthier Serge,
Quirion Rémi
Publication year - 1996
Publication title -
journal of comparative neurology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.855
H-Index - 209
eISSN - 1096-9861
pISSN - 0021-9967
DOI - 10.1002/(sici)1096-9861(19960520)369:1<31::aid-cne3>3.0.co;2-l
Subject(s) - biology , muscarinic acetylcholine receptor , nicotinic agonist , neuroscience , cholinergic , acetylcholine receptor , ontogeny , receptor , muscarinic acetylcholine receptor m4 , endocrinology , genetics
The ontogenic profiles of several cholinergic markers were assessed in the rat brain by using quantitative in vitro receptor autoradiography. Brain sections from animals at different stages of development were processed with [ 3 H]AH5183 (vesamicol; vesicular acetylcholine transport sites), [ 3 H] N ‐methylcarbamylcholine (α 4 β 2 nicotinic receptor sites), [ 3 H]hemicholinium‐3 (high‐affinity choline uptake sites), [ 3 H]3‐quinuclidinyl benzilate (total population of muscarinic receptor sites), [ 3 H]4‐DAMP (muscarinic M 1 /M 3 receptor sites), [ 3 H]pirenzepine (muscarinic M 1 receptor sites), and [ 3 H]AF‐DX 116 and [ 3 H]AF‐DX 384 (muscarinic M 2 receptor sites) as radiolabeled probes. The results revealed that, by the end of the prenatal period (embryonic day 20), the densities of nicotinic receptor and vesicular acetylcholine transport sites already represented a considerable proportion of those observed in adulthood (postnatal day 60) in different laminae of the frontal, parietal, and occipital cortices, in the layers of Ammon's horn fields and the dentate gyrus of the hippocampal formation, as well as in the amygdaloid body, the olfactory tubercle, and the striatum. In contrast, at that stage, the densities of total muscarinic, M 1 /M 3 , M 1 , and possibly M 2 receptor and high‐affinity choline uptake sites represent only a small proportion of levels seen in the adult. Differences were also observed in the postnatal ontogenic profiles of nicotinic, muscarinic, vesamicol, and high‐affinity choline uptake sites. For example, between postnatal weeks 3 and 5, the levels of M 1 /M 3 and M 1 sites were at least as high as in the adult, whereas M 2 and high‐affinity choline uptake site densities appeared to be delayed and to reach adult values only after postnatal week 5. With regard to cholinergic innervation in the developing rat brain, the present findings suggest a temporal establishment of several components of the cholinergic systems. The first components are the vesicular acetylcholine transporter and nicotinic sites; these are followed by M 1 /M 3 and M 1 sites and, finally, by M 2 and high‐affinity choline uptake sites. © 1996 Wiley‐Liss, Inc.