The effect of mercury compounds on the functional state of rat brain muscarinic acetylcholine receptors

Original article


Mohiey Eldin A. EL-Desouky, Tahar A. Soleiman

Toxicology and Forensic Department, Faculty of Medicine, Elfateh University

JMJ Vol. 2, No. 2 (September 2002): 65-67


The effect of treatment of methyl mercury (CH3 Hg) and mercuric chloride (HgCl2) on the binding properties of muscarinic acetyl choline receptors in rat brain synaptosomes was investigated using the potent L-(3H) quinulinybenzilate ({3H}QNB) acetylcholine receptor antagonist to study binding to the muscarinic receptors. Mercurial compounds were administered orally in a dose of 8mg / kg daily for 5 successive days, {3H} QNB binding decreased markedly with maximum inhibition of about 48% in 12 and 18days after the last treatment with CH3 Hg and HgCl2, respectively. On the other hand, the ability of the muscarinic receptors agonist carbamylcholine to displace {3H} QNB binding was not affected by mercurial compounds. It was concluded that organic mercury caused maximum inhibition of {3H} QNB- binding faster then inorganic mercury but, also, decline to normal level faster and both of them do not have differential effect on agonist or antagonist binding sites.

Keywords: Muscarinic acetylcholine receptors, Methyl mercury (CH3 Hg), Mercuric chloride (HgCl2)