Department of Environmental Toxicology

Professor:
Hideki Igisu
, MD, Ph.D.

Associate Professor:
Masato Matsuoka
, MD, Ph.D.

Research Activities:

  1. Mechanisms of effects of neurotoxins

  2. Studies on "peripheral markers" of neurotoxins

  3. Studies on cerebral protection

Key words: neurotoxins, brain metabolism, cerebral protection, energy metabolism, immediate early genes

    Research activities are focused on the mechanisms of effects of neurotoxic chemicals and suppression of them (prevention of intoxication with neurotoxins).

  1. Effects on brain metabolism, especially those on energy metabolism, impairment of cellular membranes, and changes of the expression in immediate early genes (c-fos etc) caused by various chemicals such as acrylamide, pentachlorophenol, carbon monoxide and ammonia are studied.

  2. For early detection of invasion of neurotoxic chemicals, effects on "peripheral markers" (erythrocytes, lymphocytes and serum) are examined along with effects on the nervous system.

  3. Factors (chemicals) that can protect the brain from various insults such as neurotoxins, ischemia and seizures are studied. Recently much attention has been paid on effects of carnitine.

  4. Experiments on preservation of isolated lungs are also done, considering possible application for studies on penetration of toxic chemicals (carbon monoxide etc) through the lungs.

Selected recent publications:

Matsuoka M & Igisu H (1992): Preservation of energy metabolites by carnitine in the mouse brain under ischemia. Brain Res 590: 334-336

Matsuoka M & Igisu H (1993): Comparison of effects of L-carnitine, D-carnitine and acetyl-L-carnitine on neurotoxicity of ammonia. Biochem Pharmacol 46: 159-164

Igisu H (1993): Haemolysis of human erythrocytes by pentachlorophenol and its suppression by albumin. Brit J Indust Med 50: 378-379

Igisu H, Hamasaki N & Ikeda M (1993): Highly cooperative inhibition of acetylcholinesterase by pentachlorophenol in human erythrocytes. Biochem Pharmacol 46: 175-177

Kohriyama K, Matsuoka M & Igisu H (1994): Effects of acrylamide and acrylic acid on creatine kinase activity in the rat brain. Arch Toxicol 68: 67-70

Matsuoka M, Igisu H, Tanaka I, Hori H & Koga M (1994): Effects of hypo- and hyperglycemia on brain energy metabolites in mice exposed to carbon monoxide. Toxicol Lett 73: 135-143

Shiraishi T, Igisu H & Shirakusa T (1994): Effects of pH and temperature on lung preservation: A study with an isolated rat lung reperfusion model. Ann Thoracic Surg 57: 639-643

Matsuoka M & Call KM (1995): Cadmium-induced expression of immediate early genes in LLC-PK1 cells. Kidney Int. 48: 383-389

Igisu H, Matsuoka M & Iryo Y (1995): Protection of the brain by carnitine. J Occup Health 37: 75-82

Matsuoka M, Matsumura H & Igisu H (1996): Creatine kinase activities in brain and blood: possible neurotoxic indicator of acrylamide intoxication. Occup Environ Med 53: 468-471

Activities of each staff in the department:

Professor and chairman : Hideki Igisu

Associate Professor : Masato Matsuoka