| Project/Area Number |
13640686
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Single-year Grants |
|---|
| Section | 一般 |
|---|
| Research Field |
動物生理・代謝
|
|---|
| Research Institution | Osaka City University |
|---|
Principal Investigator |
NUMATA Hideharu Osaka City University, Graduate School of Science, Professor, 大学院・理学研究科, 教授 (70172749)
|
|---|
| Co-Investigator(Kenkyū-buntansha) |
SHIGA Sakiko Osaka City University, Graduate School of Science, Associate Professor, 大学院・理学研究科, 助教授 (90254383)
|
|---|
| Project Period (FY) |
2001 – 2003
|
| Project Status |
Completed (Fiscal Year 2003)
|
| Budget Amount *help |
¥3,500,000 (Direct Cost: ¥3,500,000)
Fiscal Year 2003: ¥500,000 (Direct Cost: ¥500,000)
Fiscal Year 2002: ¥700,000 (Direct Cost: ¥700,000)
Fiscal Year 2001: ¥2,300,000 (Direct Cost: ¥2,300,000)
|
|---|
| Keywords | adult diapause / neurosecretory cells / Protophormia terraenovae / pars intecerebralis / pars lateralis / corpus allatum / juvenile hormone / ハエ / FMRFアミド / 休眠 |
|---|
| Research Abstract |
The present study was performed with an aim to investigate neural mechanisms underlying reproductive diapause in the blow fly, Protophormia terraenovae. In vitro synthetic activities of juvenile hormones (JH) were examined using a radiochemical assay in diapause females and reproductive females. JH synthetic activities increased in females reared under diapause-averting conditions and remained low in previtellogenic females reared under diapause-inducing conditions. A decrease in the JH production rate is a cause of diapause induction. JH synthetic rate after removal of the pars intercerebralis (PI) and pars lateralis (PL) neurons suggested that these neurons do not directly mediate changes in the JH production rate, but regulate ovarian development cooperatively with some unknown allatostatic and allatotropic factors. Morphological and electrical properties of PI and PL neurons were examined by intracellular recording and staining. Three types of PI and two types of PL neurons were identified. Among these neurons, one PI neuron showed significant differences in spike durations and one PL neuron in spike heights between diapause-inducing and diapause-averting conditions. FMRFamide, β-pigment-dispersing hormone, corazonin and cholecystokinin-like peptides were immunocytochemically revealed in the PI or PL neurons. FMRFamide and cerebral lobes weakly suppressed JH biosynthetic rates in vitro. The present study morphologically and electrophysiologically characterized PI and PL neurons, and showed candidates for factors controlling JH synthetic rates in neural mechanisms for reproductive diapause in P.terraenovae.
|
