Effects of trivalent and petavalent antimony compounds on cholinergic activities in brain tissue

• Published in: Japanese Journal of Pharmacology Vol. 58; no. suppl.2; p. 366
• Main Authors: Nakagawa, Akemi, Kobayashi, Haruo, Suzuki, Tadahiko, Ono, Naoko, Motegi, Akira, Kasashima, Yoshinori
• Format: Journal Article
• Language: English
• Published: The Japanese Pharmacological Society 1992
• ISSN: 0021-5198; 1347-3506
• DOI: 10.1016/S0021-5198(19)49592-9

Some antimonials have been used as helmintics, especially for the treatment of filaliosis such as cerebrospinal filaliosis in veterinary medicine. The effects of antimony compounds, a trivalent (antimony K-tartrate, SbPT) and a pentavalent (Na-oxiantimony gluconate, Sb_2 SG), on the cholinergic parameters in mouse cerebral cortex were investigated in vitro. Both antimonials (10-6 -10-4 M) did not show significant effects on the activity of acetylcholinesterase and on the binding of 3 H-quinuclidinyl benzilate to muscarinic acetylcholine (ACh) receptors. SbPT inhibited the activity of choline acetyl-transferase at concentrations of 10-6 to 10-4 M by up to 25% in a dose-dependent manner and Sb_2 SG only at 10-4 M by 25%. Both antimonials (10-6 -10-4 M) caused an inhibitory effect on high-affinity uptake of choline into synaptosomes in a dose-dependent manner by up to 53% (SbPT) and 46% (Sb_2 SG). SbPT and Sb_2 SG also inhibited low-affinity upta in a similar manner by up to 34% (SbPT) and 50% (Sb_2 SG). Both antimonials (10-6 -10-4 M) did not show significant effects on K+ -induced release of and synthesis of ACh of cortical slices. The efficacy of inhibitory effects of SbPT was generally bigger than that of Sb_2 SG. These results suggest that an antimonial, especially a trivalent, influences the cholinergic system suppressively mainly by inhibiting the synthesis of ACh.