Alonso I A, Prieto J C, Arilla E
Department of Biochemistry and Molecular Biology, Medical School, University of Alcala, Madrid, Spain.
Psychopharmacology (Berl). 1993;110(1-2):103-9. doi: 10.1007/BF02246957.
The acute and chronic administration of diisopropylfluorophosphate (DFP), an inhibitor of acetylcholinesterase (AChE), and of atropine, a blocker of muscarinic cholinergic receptors, did not affect somatostatin-like immunoreactivity (SLI) content in the frontoparietal cortex and hippocampus of rats. Acute and chronic DFP administration increased the number of specific 125I-Tyr11-somatostatin (125I-Tyr11-SS) receptors in synaptosomes from the frontoparietal cortex but not in those from the hippocampus and did not change the affinity constant. This increase in 125I-Tyr11-SS binding was not due to a direct effect of DFP on somatostatin (SS) receptors since no rise of binding was produced by high concentrations of DFP (10(-5) M) when added in vitro. The increase could be blocked by pretreatment with atropine. The acute administration of atropine alone had no observable effect on the number of SS receptors. However, repeated atropine administration produced a significant decrease in the 125I-Tyr11-SS binding in synaptosomes from the frontoparietal cortex but not in those from the hippocampus although the affinity constant was unchanged. The results suggest that interactions between somatostatinergic and cholinergic receptors may be important in the rat frontoparietal cortex.
乙酰胆碱酯酶（AChE）抑制剂二异丙基氟磷酸酯（DFP）以及毒蕈碱型胆碱能受体阻断剂阿托品的急性和慢性给药，均未影响大鼠额顶叶皮质和海马体中生长抑素样免疫反应性（SLI）的含量。急性和慢性给予DFP可增加额顶叶皮质突触体中特异性125I-酪氨酸11-生长抑素（125I-酪氨酸11-SS）受体的数量，但对海马体突触体中的受体数量没有影响，且不改变亲和常数。125I-酪氨酸11-SS结合的这种增加并非由于DFP对生长抑素（SS）受体的直接作用，因为在体外加入高浓度DFP（10(-5) M）时未产生结合增加。这种增加可被阿托品预处理阻断。单独急性给予阿托品对SS受体数量没有可观察到的影响。然而，反复给予阿托品会使额顶叶皮质突触体中125I-酪氨酸11-SS的结合显著减少，但对海马体突触体中的结合没有影响，尽管亲和常数未变。结果表明，生长抑素能受体与胆碱能受体之间的相互作用在大鼠额顶叶皮质中可能很重要。
