Direct Absorption of Methyl Mercury by Lymph

Abstract

Methyl mercury is contained in fish and seafood products and is taken up into the body in food. While the central nervous system is known as a target organ, methyl mercury also induces autoimmunity and acts as a potent immunosuppressor. The aim of the present study is to know whether methyl mercury is directly absorbed by lymph. Conscious rats were infused with methyl mercury (4 mg/kg) via duodenal tubing as a single pulse infusion, followed by the continuous infusion of saline, and lymphatic fluids were continuously collected from the thoracic lymph duct every 30 min until 360 min after infusion. Mercury was detected immediately after infusion, and total mercury contents in lymph gradually increased until 90-120 min, remained steady, and then gradually decreased until 360 min; however, the amount of mercury collected during 330-360 min was about twofold higher than during 0-30 min. The amount of cumulative mercury in lymph at 360 min was 1.4 μg. In contrast, blood mercury concentration was 2.4 μg/ml 5 min after infusion, with the value at 360 min being 12.6 times higher than at 5 min. Plasma mercury concentration was 56 ng/ml at 5 min, with hundreds of nanograms per milliliter of mercury detected until 360 min. From the present study, it is concluded that some methyl mercury is directly absorbed by lymph and remains steady 6 h after infusion.

Impaired aquaporins expression in the gastrointestinal tract of rat after mercury exposure

“…CH 3 Hg is considered a probable carcinogen for humans (IARC, ). It exerts its toxic effect in the central nervous tissue (Nagashima, ), the immune system and increases the risk for heart diseases (Häggqvist et al ., ; Havarinasab and Hultman, ; Murota et al ., ; Pheng et al ., ; Yaginuma‐Sakurai et al ., ). Regarding Hg(II), the gastrointestinal tract and the kidney are the primary target organs and several toxic effects have been described at the cardiovascular, neural, hepatobiliary and immunologic level (Bridges and Zalups, ; Zahir et al ., ).…”