Marmol F, Puig-Parellada P, Forn J
Unit of Pharmacology, Therapeutics and Clinical Pharmacology, Faculty of Medicine, University of Barcelona, Spain.
Methods Find Exp Clin Pharmacol. 1992 Oct;14(8):623-8.
The possible involvement of lithium in the mechanism of action of norepinephrine has been studied in electrically-stimulated preparations isolated from guinea pig myenteric plexus. Results show that concentrations of lithium above 0.5 x 10(-2) M significantly inhibit the norepinephrine effect. The results obtained when preparations were preincubated with alpha-adrenergic blocking agents (phenoxybenzamine and phentolamine) suggest a beta-adrenergic action of lithium since these substances induced 74% and 37% inhibition of the lithium effects, respectively. When preparations were preincubated with beta-adrenergic blocking agents (propranolol, toliprolol, atenolol and sotalol) the action of lithium was unchanged. A phosphodiesterase inhibitor also led to 50% inhibition of the lithium effects. These results, together with the fact that the adenylate cyclase cAMP system is linked directly to the beta-adrenoceptors, suggest that the inhibitory action of lithium on norepinephrine, in this preparation, is related to its beta-adrenergic action, which agrees with the results obtained in brain by other authors.
锂在去甲肾上腺素作用机制中的潜在参与情况已在从豚鼠肠肌丛分离出的电刺激制剂中进行了研究。结果表明，浓度高于0.5×10（-2）M的锂会显著抑制去甲肾上腺素的作用。当制剂与α-肾上腺素能阻断剂（酚苄明和酚妥拉明）预孵育时获得的结果表明锂具有β-肾上腺素能作用，因为这些物质分别诱导了74%和37%的锂效应抑制。当制剂与β-肾上腺素能阻断剂（普萘洛尔、托利洛尔、阿替洛尔和索他洛尔）预孵育时，锂的作用未发生变化。一种磷酸二酯酶抑制剂也导致了50%的锂效应抑制。这些结果，连同腺苷酸环化酶cAMP系统直接与β-肾上腺素能受体相连这一事实，表明在该制剂中锂对去甲肾上腺素的抑制作用与其β-肾上腺素能作用有关，这与其他作者在大脑中获得的结果一致。
