| Abstract: | 3H]-dihydroalprenolol was used to examine the development of beta-adrenoceptors in the cerebellum of weaver, reeler, staggerer, and jimpy neurologically mutant mice and their normal counterparts. In normal animals the greatest increase in 3H] binding occurred during the postnatal interval of 10-15 days, and maximum values were obtained at about 3 weeks. Binding was saturable with an apparent dissociation constant of 0.26 nM, and the affinity of 3]-dihydroalprenolol for its receptor did not change significantly during development. 3H]-dihydroalprenolol binding was significantly reduced in weaver, reeler, and staggerer (14-22% of control values) at 20 days, but not in the jimpy mutant. These results are discussed in relation to the ontogeny of beta-adrenoreceptors with the known noradrenergic innervation of the cerebellum, and to the paucity of both granule neurons and myelination which occurs in the neurological mutants. |
