Kinetic studies of vitellogenin metabolism in the elasmobranch Scyliorhinus canicula L.

Abstract

1. 1. The appearance of vitellogenin in the plasma of adult female Scyliorhinus canicula and its subsequent disappearance and conversion into yolk granules were monitored by an isotopic method. Rates of vitellogenin synthesis in different fish were compared. 2. 2. There was considerable individual variation in the rate of synthesis and in the plasma half-life of vitellogenin; measured values of the latter ranged from 132 to 303 hr (mean 216 hr) at 7 ± 2°C. 3. 3. Winter temperature stimulated vitellogenin synthesis in midsummer, but winter photoperiod did not do so. 4. 4. Captivity without food for 22 days reduced the rate of vitellogenin synthesis in summer but had no effect in winter.