an alternative for T. rubripes for Japanese dishes in the near
future, since the number of natural T. rubripes, are quickly
decreasing.
The present electrophysiological bioassay confirmed the
previous observations made with mouse bioassay (Noguchi
and Arakawa, 2008) and provided accurate contents of the
toxin in the muscle (0.19–1.59 mg TTX/g tissue), and liver
(1.23–62.13 mg TTX/g tissue) in five different kinds of puffer.
An electrophysiological bioassay of TTX actions on INa, from
a functional point of view, would be a more useful method
to consider the safety of all tissues of puffer as food.
In addition, from the ethical point of view, this method has
an advantage, since several hundred CA1 pyramidal
neurons could be isolated from the hippocampus of a single
rat or mice, compared with the large number of mice for
the mouse bioassay.
Acknowledgments
The authors thank Dr. K.E. Creed for her valuable
comments on the manuscript. This work was supported by
grant to N. Akaike from Kumamoto Health Science
University.
Conflict of interest statement
There are no conflicts of interest