|Budget Amount *help
¥1,200,000 (Direct Cost : ¥1,200,000)
Fiscal Year 2000 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1999 : ¥700,000 (Direct Cost : ¥700,000)
A fresh water coelenterate Hydra shows the feeding behavior after stimulation by reduced glutathione. The behavioral response is modified by a small amount of biologically active substances in the bathing medium. The modification is observed at different stimulatory conditions by each substance. First, we have investigated the cultural conditions under which the modification by biologically active substances is observed reproducibly. We have found salt compositions of the hatching medium, in which prey is hatched, are important for the modification of the hydra response.
Since the hydra behavioral test is so sensitive to biologically active peptides, it is expected to be useful for the investigation of these substances in the biological specimens, which sometimes are available only small amount. We found a TGF-beta activity in the rat cerebrospinal fluid (CSF) of the fatigued rat after forced swimming. In another study, we found the diazepam binding inhibitor (DBI) increased in the rat CSF after quinine stimulation to the oral cavity. We can detect these changes in the biologically active peptides and identify the peptide using this hydra response system easier than with other investigation methods for the detection of biologically active peptides. These examples show usefulness of the hydra response to examine biologically active substances in the small amount of biological samples.
Currently, we examine the hydra response by observing the behavior by a binocular and determine the response. All are human things. This makes the assay to be very difficult to practice. Then we develop a computer-assisted system for the assay. We have completed to develop necessary computer programs to acquire digital images from a CCD camera, to calculate image parameters, and analyze these image parameters.