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HORMONAL CONTROL OF OOCYTE MATURATION IN ARENICOLA MARINA L. (ANNELIDA, POLYCHAETA): III. INVOLVEMENT OF CA
1Université des Sciences et Techniques de Lille I, Service de Biologie Animale, Laboratoire d'Endocrinologie Comparée des Invertébrés (Prof. M. DURCHON) (L. A. CNRS No. 148), B. P. 36, 59650 - Villeneuve d'Ascq, FRANCE.
Development, Growth & Differentiation
|June 7, 2023
Summary
In Arenicola marina, oocyte maturation is triggered by a brain hormone that likely increases intracellular calcium. Reducing agents also initiate meiosis reinitiation, suggesting a role for -SH/-SS- groups.
Area of Science:
- Reproductive Biology
- Marine Invertebrate Zoology
- Cellular Physiology
Background:
- Oocytes of Arenicola marina arrest at prophase I until spawning.
- Hormonal control of oocyte maturation involves brain extracts, leading to metaphase arrest until fertilization.
Purpose of the Study:
- Investigate the role of calcium in Arenicola marina oocyte maturation.
- Explore the involvement of -SH/-SS- groups in meiosis reinitiation.
Main Methods:
- In vitro incubation of oocytes with brain extract.
- Treatment with various drugs affecting calcium permeability and concentration (tetracaine, procaine, D-600, verapamil, propranolol, oxprenolol, lanthanum chloride, ionophore A23187).
- Exposure to disulfide reducing agents (dithiothreitol, 2,3-dimercaptopropanol).
Main Results:
- Drugs altering calcium permeability and calcium deprivation induced oocyte maturation.
- Ionophore A23187 did not induce maturation.
- Disulfide reducing agents also triggered oocyte maturation.
Conclusions:
- The brain hormone likely regulates oocyte maturation by increasing intracellular free calcium concentration.
- -SH/-SS- groups are suggested to be important for meiosis reinitiation in Arenicola marina oocytes.
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