1989 Fiscal Year Final Research Report Summary
STUDY OF NEURONAL MECHANISMS UNDERLYING THE DEVELOPMENT OF INSECT VISION AND ITS PLASTICITY IN ONTOGENETIC PROCESS
| Project/Area Number |
63540578
|
|---|
| Research Category |
Grant-in-Aid for General Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Research Field |
動物発生・生理学
|
|---|
| Research Institution | NAGASAKI UNIVERSITY |
|---|
Principal Investigator |
MIMURA Keiichi NAGASAKI UNIVERSITY FACULTY OF LIBERAL ARTS, PROFESSOR, 教養部, 教授 (20039754)
|
|---|
| Project Period (FY) |
1988 – 1989
|
| Keywords | Insect / Fly / Pattern vision / Plasticity / Cytochrome oxidase histochemistry / HPLC / Biogenic amines / Experience-dependency |
|---|
| Research Abstract |
It has been demonstrated that the development of visual pattern discrimination depends on the visual experience after birth. Such experience-dependency was demonstrated even in insects (fly) in my previous experiments. Purpose of this research project was to get a clue for understanding the plastic development through behavioral, histocheminal and biochemical studies.
1. Detailed conditions of visual experience needed for the development of pattern discrimination Visual experience for at least 5 hours immediately after emergence, normal activity of visual system for very short period (15 minutes) immediately after the visual experience, and maintenance of neuronal activity for 5 hours thereafter were needed as the minimum conditions for the development. Results were also certified by injection of some inhibitors of protein synthesis.
2. The effect of visual deprivation using cytochrome oxidase histochemistry Elevated cytochrome oxidase reactivity has been correlated with neuronal and syn
… More
aptic activity. The cytochrome oxidase reactivity was higher in the optic lobe of the intact eye than in that of the light-deprived eye. This difference of the reactivity appeared after the 6th day of post-emergence. Any difference was not observed in the central part of the brain. Results show that the visual information processing is done in the optic lobe only, and that the development of visual function is due to a plastic modification of synaptic transmission.
3. Analysis of biogenic amines in the optic lobe by HPLC Biogenic amines in the optic lobe were determined using HPLC with electrocheminal detection. Amounts of two substances among all optic lobe-specific substances increased during a definite period of post-emergence when the fly had experience of light, while no increase was seen when it was put in constant darkness. It is suggested that the two substances are involved in synaptic transmission and then these subserve the plastic development of pattern discrimination, although the substances were not identified yet. Less
|
