title: Autoradiographic localization of beta 1 and alpha 1-adrenoceptors in the midbrain and forebrain of normal and reeler mutant mice.
abstract: The distribution of alpha-1 and beta-1 adrenoceptors has been studied in the midbrain and forebrain of normal and reeler mutant mice, using autoradiographic visualization of radioiodinated HEAT and ICYP, respectively. All cortical structures and nuclear groups of the murine forebrain and midbrain bind ICYP and HEAT. For each ligand, there is substantial regional variation in binding density and these variations tend to observe boundaries between nuclei or cortical regions or the stratification of cortical regions. Regional variations in binding densities are generally different for ICYP and HEAT. Binding sites for ICYP are distributed densely throughout all fields of the neocortex (particularly, layers I-III greater than VI) and paleocortex, the striatum, pallidum, substantia nigra and superficial strata of the superior colliculus. Dense concentrations of binding sites for HEAT in cortical structures, by contrast, are limited to frontal (all layers except IV) and anterior cingulate regions of the neocortex and, as with ICYP, the stratum lacunosum-moleculaire of the regio superior of the hippocampal formation. In subcortical structures, again in contrast to the pattern with ICYP, binding density is greatest in the principal nuclei of the dorsal thalamus and the septal nuclei. The regional binding patterns of both ICYP and HEAT in the reeler brain are identical to those in the normal animal. Differential laminar binding patterns within the neocortex are approximately inverted in the two genotypes, however. Thus, binding of ICYP is densest in an inner zone of the mutant, but in the outer 3 layers of the normal neocortex. Binding of this ligand is of relatively lower density in an outer zone of the mutant and in the inner 3 layers of the normal neocortex. Similar inversions are characteristic of the laminar binding patterns of HEAT in the frontal, primary sensory and associational cortical regions of the two genotypes where densest binding is encountered superficially in reeler but at deeper levels of the normal neocortex.
mesh_terms: D000818:Animals; D001345:Autoradiography; D001921:Brain / Q000378:metabolism*; D020120:Iodocyanopindolol; D008032:Limbic System / Q000378:metabolism; D008636:Mesencephalon / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D008818:Mice, Neurologic Mutants; D010627:Phenethylamines / Q000378:metabolism; D010869:Pindolol / Q000031:analogs & derivatives / Q000378:metabolism; D011942:Receptors, Adrenergic, alpha / Q000378:metabolism*; D011943:Receptors, Adrenergic, beta / Q000378:metabolism*; D013687:Telencephalon / Q000378:metabolism; D044024:Tetralones; D013787:Thalamic Nuclei / Q000378:metabolism
chemical_list: D010627:Phenethylamines; D011942:Receptors, Adrenergic, alpha; D011943:Receptors, Adrenergic, beta; D044024:Tetralones; D020120:Iodocyanopindolol; C048008:2-(beta-(3-iodo-4-hydroxyphenyl)ethylaminomethyl)tetralone; D010869:Pindolol