Moses D F, Ortí E, De Nicola A F
Brain Res. 1987 Apr 7;408(1-2):118-24. doi: 10.1016/0006-8993(87)90363-5.
Studied under in vivo conditions, uptake of [3H]corticosterone (CORT) by purified cell nuclei of the hippocampus was much higher than in the spinal cord, although the latter may contain in cytosol up to 50% of glucocorticoid receptors found in cytosol of hippocampus. Experiments were undertaken to explain these differences. First, the in vivo affinity of receptors for exogenous CORT was comparable in both tissues. Second, an inhibitor of translocation, although present, was not preferentially concentrated in the spinal cord as compared to the hippocampus. However, the sensitivity towards RNAase A, an enzyme that increased binding to DNA-cellulose (taken as a measure of increased affinity for nuclear components), was preserved in the hippocampus but absent in the cord. We discuss the possibility that refractoriness to RNAase A may play a role in the reduced nuclear uptake of [3H]CORT shown by the spinal cord in vivo, but also consider possible that heterogeneity of receptor types binding CORT in the spinal cord and hippocampus may account for the differences observed in both tissues.
在体内条件下进行研究时，海马体纯化细胞核对[3H]皮质酮（CORT）的摄取远高于脊髓，尽管后者胞质溶胶中糖皮质激素受体的含量可达海马体胞质溶胶中发现的50%。开展了实验以解释这些差异。首先，两种组织中外源CORT受体的体内亲和力相当。其次，虽然存在转运抑制剂，但与海马体相比，它在脊髓中并非优先富集。然而，海马体中保留了对核糖核酸酶A（一种增加与DNA纤维素结合的酶，以此作为对核成分亲和力增加的指标）的敏感性，而脊髓中则没有。我们讨论了对核糖核酸酶A不敏感可能在脊髓体内[3H]CORT核摄取减少中起作用的可能性，但也考虑了脊髓和海马体中结合CORT的受体类型异质性可能解释在这两种组织中观察到的差异的可能性。
