Insect neurosecretion : putative carrier proteins and regulative agents.
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| Other Authors: | , , , |
| Format: | Thesis Book |
| Language: | English |
| Published: |
1983.
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| Subjects: | |
| Online Access: | Link to ProQuest Copy Link to OAKTrust copy |
| Abstract: | Using ('35)S-cysteine labeling and a molecular weight of ca. 10,000 daltons, several putative neurophysins (NP), similar to the neurophysins in the vertebrate pituitary gland, were isolated from homogenates of the brain and CC-CA of Blaberus discoidalis by standard gel permeation and high performance liquid chromatography. Neurosecretory granules (NSG) were isolated from the CC-CA homogenates by differential centrifugation. From an initial isolation procedure (Evans, 1962), a final NSG enriched pellet having high hindgut stimulating hormone (HSH) activity and NP-like proteins was prepared. From a second differential centrifugation isolation procedure, two NSG containing pellets, 4,000 g and 11,000 g, were formed. The 4,000 g pellet contained NSG (mean diameter of 146 (+OR-) 6 nm) as well as other cellular debris. This pellet exhibited high HSH activity and low cytochromogenic hormone activity. It was not examined for NP. The 11,000 g pellet was highly enriched in NSG (mean diameter 103 (+OR-) 4 nm), with little other contaminating structures. This pellet was high in cytochromogenic hormone activity and low in HSH activity. No putative NP was detected in this fraction by the chromatographic methods employed. The role of biogenic amines was examined in insect neurosecretion as determined by the effect on onset of pupation in Aedes aegypti. The larvae were exposed to biogenic amines or to drugs that have known effects on biogenic amine functions. Chlorophenylalanine, methyl-p-tyrosine, and octopamine had no effect on the onset of pupation. Chlorpromazine (10 ppm) and 6-hydroxy-dopamine (100 ppm) delayed the onset of pupation. Bromocryptine accelerated pupation at 1.0 ppm but delayed pupation at 100 ppm. These results suggest that biogenic amines may regulate neurosecretory processes related to molting and metamorphosis. |
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| Item Description: | "Major subject: Entomology." Typescript (photocopy). Vita. |
| Physical Description: | x, 99 leaves : illustrations ; 29 cm |
| Bibliography: | Includes bibliographical references (leaves 87-98). |