The important object in the development
of alternative methods in the area of drug metabolism research is to predict
drug metabolism in humans. In this regard, we established E. coli and Salmonella
carrying human cytochrome P450. E. coli carrying human cytochrome P450
together with NADPH-cytochrome P450 reductase showed characteristic catalytic
properties for human cytochrome 450 with high catalytic activity. Thus,
this E. coli system can be used as a bioreactor to predict human drug metabolism.
In addition, Salmonella, which is over-expressing Salmonella Oacetyltransferase,
carrying human CYPIA2 together with the reductase was ultra-sensitive to
heterocyclic amines isolated from protein pyrolysates, indicating that
this recombinant Salmonella can be a useful tool to predict carcinogenicity
of chemicals in humans with high sensitivity.
The prediction system of chemical
toxicity has been developed by means of structure-activity relationship
based on the computerized fact database. Numbers of elements, side chains,
bonding, position of substituents, and microenvironment of side chains
were used for prediction. In the present study, Salmonella/microsome assay
was chosen as indicative of the target toxicity of chemicals. A set of
chemicals specified with mutagenicity data was retrieved, and necessary
information was extracted and transferred to the working file. Rules of
the relation between characteristics of chemical structure and the assay
result are extracted as parameters for rules by experts on the rearranged
data set. These are analyzed statistically by the discriminant analysis
and the prediction with the rules were evaluated by the elimination method.
In the symposium, present status of the usage of the toxicity prediction
system in risk assessment will be discussed.
S1- 1b. TOPKAT -Computational Toxicology Software -
TOPKAT is a software-based system
which computes and automatically validates assessments of toxic and environmental
effects of chemicals solely from molecular structure. TOPKAT employs robust
and cross-validated Quantitative Structure Toxicity Relationship (QSTR)
models for assessing various measures of toxicity. These models have been
developed from bioassay results carefully evaluated as to accuracy and
consistency of methodology. Query structure is stored stastical weights
of the molecular features idintified to retum the best least squares fit.
When the structure is submitted for toxicity assessment, TOPKAT automatically
quantifies the contributions of these features. The total of contributions
is transformed to compute the probable toxic or environmental effect of
the query structure.
Institute for Animal Experimentation,
University of Tokushima School of Medicine
It is important to use proper laboratory animal species or strains in order
to obtain accurate and reproducible experimental results, which leads to
the reduction of unnecessary animal experiments. In general, however, it
is relatively difficult to select the animai species or strains suitable
for each experimental purpose, or to these problems is the use of laboratory
animal databases through the computer network. We have recently developed
a useful database on laboratory animals which is accessible through the
computer network. I would like to talk about the usefulness of the database
especially from the viewpoint of "reduction" of laboratory animals.
S1-2b. Alternatives for Animal Experiments with Computer : Replacement of Animal Experiments with Internet Resources
Haruyuki Tatsumi, Masahiro Nakamura, Youhei Ohkawa, and Hiroki Nogawa
Department ofAnatomy, Sapporo Medical University School of Medicine
As an alternative animal experiment,
the possibilities of computer and the Intemet utilization are discussed.
To accomplish such kinds of altematives, di*~ital data should be stored
at a large scale in the world. Aiming at a large scale data storage, we
are developing researcher-friendly three-dimensional reconstruction system
connected to the Internet.
Acknowledgment : This study was partly performed through Special Coordination Funds of the Science and Technology Agency of the Japanese Government.
S1-2c. Refinment of Animal Experimentation Using Mailing Lists
Dept. Clin. Lab. Sci., Sch. Allied Health Sci., Osaka Univ.
The most simple but fundermental system on INTERNET is electronic mail (E-mail). E-mail messages deliver to almost all over the world rapidly without effort, and can be processed easily because they are electronic data. To deliver E-mail to many addresses, the system named Mailing List is most useful. It can deliver one mail to many clients automatically, and it is most important to say that we can share many information using Mailng List. Thus if we use Mailing List efficiently, we will be able to refine our experiments, particularly animal experimentation.
Pain can be assessed when it is defined
as a sensory-emotional experience produced by tissue-damaging noxious
stimuli. For animals, where a verbal description of the pain is not possible,
the pain can be inferred from physiological and behavioral changes. Although
animals lack the ability to verbally communicate their pain, they exhibit
motor behaviors and physiological responses indicative of pain. Such behaviors
include simple withdrawal reflexes and more complex learned behaviors to
avoid further exposure to noxious stimulation. Stimuli near threshold produce
minimal aversive reactions and are well tolerated by animals. It is only
when the intensity of the stimulus approaches tolerance level, animals
attempt to avoid or escape it. Simple reflexive measures such as the tail
flick, allow the anirpals to avoid noxious stimuli by escaping fro the
preceding innocuous stimuli.
S2-2. Measurement of Animal's Pain : Pharmacological Methods
Centerfor Laboratory Animal Science, Tohoku College of Pharmacy
Pain has been defmed as " an unpleasant
sensory and emotional experience associated with actual or potential tissue
damage, or described in terms of such damage" (International Association
for the Study of Pain Subcommittee on Taxonomy, 1979). Since pain is subjective
and emotional experience for each individual, it is perhaps expecting that
so much effort in animal pain valuation is devoted to the measurement of
pain perception. However, painful stimuli (noxious or aversive stimuli)
can cause both a simple and an overt self-protective behaviour in animals.
Therefore, we are able to observe and record its behaviours as nonverbal
communications of pain. The purpose of this section is to present an overview
of standardized pharmacological methods in evaluating pain in animals.
S2-3. Recognizing pain in Animai Patients
Lab. Vet. Surg. Division of Veterinary Clinical Sciences, Graduate School of Agriculture, Llfe and Science, The University of Tokyo
Pain is an complex physiological
phenomenon. It is difficult to define and even more difficult to identify
and interpret in animals. Subjective responses to pain experienced
by humans are compared to those found in animals using analogies based
on anatomical, physiological, and pathological studies, Animals feel pain
to the same extent as humans and they have a wide variation in tolerance
to pain stimuli as well. Animals may express pain or discomfort in two
ways. Excessive activity or relative lethargy are both overt reflections
of a pain state. Expression of pain may be exhibited by moaning, groaning,
crying, Iooking at the painful area, Iicking or biting, or simply a decrease
S2-4. Assessment of Animal Pain - Animal Psychological Methods
Sophia University, Department ofPsychotogy
One of the important problems when
we try to elucidate the mechanism of the generation and alleviation of
pain in animal experimentation is the way to assess the pain> i.e., what
kind of stimulus should be used as a pain stimulus (noxious stimulus) ,
and what kind of response (s) to the noxious stimulus should be used as
a criterion for the pain. In general, a noxious stimulus is defined as
one that produces defense or withdrawal mechanisms in the body. Those mechanisms
include various responses from almost stereotyped spinal responses to ones
that require the integration of more highly advanced nervous systems. Vatious
methods for assessment of animal pain have been so far developed or elaborated.
However, only one method is not sufficient for assessin*' all the aspects
of pain. It would be necessary to understand fully the characteristics
of each method for the assessment of pain (e.g., the kind of noxious stimulus,
and response (s) that is (are) produced by the noxious stimulus) , and
to compare each method carefully with other methods as the need arises.
In Korea, with the establishment
of KGLP in 1987, the researchers became more involved in animal experimentation.
However, education for the proper use of laboratory animals has not been
performed. At the beginning, animal experiments were not done on a large
scale in Korea, and therefore, there was no movement against animal experiments.
However, the public concern over the protection of animals has recently
increased and as a result, organizations such as the Society for the Prevention
of Cruelty to Animals and the Rescue Team forAnimals were organized. In
June this year, a I -hour rv program on the real state of animal experimentation
was broadcasted on MBC in Korea. The attitude of the general public in
Korea to laboratory animals is basic;ally not so different from that of
Westem people. During the last few years, we have improved the education
system for the proper use of laboratory animals in order to increase the
accuracy and reproducibility of animal experiments, and at the same time,
we have emphasized the importance of refinement of animal experimentation
whereby the suffering imposed on laboratory animals is alleviated. However,
information on the importance of animal experimentation is not fully spreading
among the general public, and therefore, to date they
have not been fully convinced of the rationale of sacrificing lives of
laboratory animals for the benefit of human welfare.
I think that people working in the field of laboratory animal science should endeavor to educate the general public so that they can understand the importance of animal experimentation and the "3 R" principle. I would like to talk about the present state of the use of laboratory animals and the movement of animal protection in Korea, and also speculate when radical movement against animal experiments like Westem countries will happen in Korea.
S3-2. Altemative to Animal Experiments in The Eyes of Chinese
Pan Tien Mei
Guangdong Medical LaboratoryAnimal Center, Guangzhou, China
Animal experimentation is indispensable
for the development of biomedical studies. Most Chinese people think that
animal-dependent biomedical research will be necessary also in the future
because much more research subjects still remain to be done. Animal rights
movements in Western countries are regarded as too extreme by Chinese people.
However. Chinese researchers can understand the "3 R" tenet (or alternative
to animal experiments). According to the questionnaires which have been
recently sent to 102 researchers and technologists working at 15 biomedical
research institutes in Guangdong province, 98% people approved the use
of analgesics and anesthetics to alleviate the fear and pain of laboratory
animals; and 85% people thought that some of the animal-dependent studies
could be replaced by non-animal tests such as cell culture and computer simulation. In China, the importance of animal experimentation and to educate the general public actively so that they can understand the importance of animal experimentation.
S3-3. Alternatives to Animal Experiments in The Eyes of Taiwanese and Malaysians
Ooi Hong Kean
National Chung Hsing University, Taiwan
It goes without saying that the view of animals is considerably different between Asians and Westerners. It may be probably due to the difference in the social background such as tradition, custom and culture. In Asia, there are many countries with diverse social backgrounds. I would like to talk about the present state of alternative to animal experimentation in Taiwan and Malaysia. In Taiwan, there are about two million dogs, half of which are thought to be stray dogs. Although the issue of stray dogs is a big social problem in Taiwan, there is a group which opposes killing of stray dogs. However, according to the questionnaires sent to 73 veterinary students in Taiwan, 97% students thought that animal experimentation was necessary ; 73% students approved the "reuse" of captured stray dogs for animal experiments. The above results can be regarded as a reflection of the view of animals cherished by the general public in Taiwan. In Taiwan, Iaboratory animal facilities are not necessarily in good condition as compared with those in Japan, and it will take some more time for Taiwanese to "digest" the concept of alternative to animal experimentation (or the "3R" principle). Malaysia consists of many races, and each race possesses their original language and society. The view of animals cherished by Malaysians is rather dependent upon their religions : Malaysian people are Islamites and not only avoid the swine, but also strongly regard dogs as filthy animals, and rodents as pests injurious to farm products. Indian and