Booze R M, Crisostomo E A, Davis J N
Department of Pharmacology, University of Kentucky College of Medicine, Lexington 40536-0084.
Synapse. 1993 Mar;13(3):206-14. doi: 10.1002/syn.890130303.
Species differences in the distribution of beta-adrenergic receptors in the hippocampal and retrohippocampal regions of rats and guinea pigs were examined using in vitro autoradiographic techniques. beta 1-receptors were found in the hippocampal area CA1 of both species, although guinea pigs had significantly lower receptor densities in comparison to rats. In guinea pigs, beta 2-adrenergic receptors were predominant in hippocampal area CA1. Hippocampal area CA3 had very low levels of beta 1- and beta 2-receptors in both species. The retrohippocampal area was also found to have a distinct topographic distribution of beta-receptors. In rats, the subiculum and parasubiculum (layers II-III) were heavily labeled for beta 1-receptors; in contrast, guinea pigs had few receptors in these regions. beta 2-receptors were particularly prominent in the parasubicular region in rats. The entorhinal cortex laminae was found to contain beta-receptors in both rats and guinea pigs. Immunohistochemical techniques were used to compare the pattern of catecholaminergic innervation with the receptor distribution within each hippocampal subregion. Despite the general lack of beta-receptors in area CA3, abundant catecholamine immunoreactive fibers were observed in CA3 of rat and guinea pig hippocampus. Significant species differences were found in the distribution of hippocampal beta-adrenergic receptor subtypes, and moreover, in both species the distribution of beta-adrenergic receptors did not coincide with the pattern of hippocampal adrenergic innervation.
采用体外放射自显影技术，研究了大鼠和豚鼠海马及海马后区域β-肾上腺素能受体分布的种间差异。在两个物种的海马CA1区均发现了β1受体，不过与大鼠相比，豚鼠的受体密度显著更低。在豚鼠中，海马CA1区β2-肾上腺素能受体占主导。两个物种的海马CA3区β1和β2受体水平都非常低。还发现海马后区域β受体具有独特的拓扑分布。在大鼠中，下托和副下托（II-III层）β1受体标记密集；相比之下，豚鼠在这些区域的受体很少。β2受体在大鼠的副下托区域尤为突出。发现内嗅皮质层在大鼠和豚鼠中均含有β受体。采用免疫组织化学技术比较了每个海马亚区内儿茶酚胺能神经支配模式与受体分布。尽管CA3区普遍缺乏β受体，但在大鼠和豚鼠海马的CA3区均观察到丰富的儿茶酚胺免疫反应性纤维。在海马β-肾上腺素能受体亚型的分布上发现了显著的种间差异，此外，在两个物种中，β-肾上腺素能受体的分布均与海马肾上腺素能神经支配模式不一致。
