...S. L. Steele; P. H. Yancey; P. A. Wright SUMMARY Marine elasmobranchs retain relatively high levels of urea to counterbalance the osmotic strength of seawater. Oviparous species, such as the little skate Raja erinacea , release encapsulated embryos that hatch after about 9 months on the seafloor...

... skate Raja erinacea Urea retention is the cornerstone of the marine elasmobranchs'osmoregulation strategy. A relatively high concentration of urea and trimethylamine oxide (TMAO) in the extracellular fluid allows these fishes to be slightly hyperosmotic to the marine environment( Smith, 1936...

... transporter in the kidney of the dogfish. We examined mechanisms of urea transport in the kidney of the little skate Raja erinacea using an isolated brush-border membrane vesicle preparation. Urea uptake by brush-border membrane vesicles is by a phloretin-sensitive, non-saturable uniporter in the dorsal...

.... To investigate whether Ca i 2+ signaling is similarly organized in elasmobranch epithelia, we examined Ca i 2+ signaling patterns and InsP3 receptor (InsP3R) expression in hepatocytes isolated from the little skate, Raja erinacea . Ca i 2+ signaling was examined by confocal microscopy, InsP3R expression...

...Gregory O. Hjelmstad; Geoffrey Parks; David Bodznick ABSTRACT The dorsal granular ridge (DGR) of the elasmobranch vestibulolateral cerebellum is the source of a parallel fiber projection to the electrosensory dorsal nucleus. We report that the DGR in Raja erinacea contains a large percentage...

... responsible for common mode suppression. Our results are in accord with previous indications that ascending efferent neurones of the medullary nucleus are monosynaptically activated from the ipsilateral electrosensory nerves and project to the midbrain. We demonstrate that in Raja erinacea , as has been...

..., Middletown, CT 06457, USA † Present address: Department of Zoology, University of Auckland, Auckland, New Zealand. 23 6 1992 © 1992 by Company of Biologists 1992 elasmobranch electroreception noise suppression reafference medulla Raja erinacea Elasmobranch fishes...

...Bernd Pelster; William E. Bemis ABSTRACT The development of the cardiovascular system has been analysed in embryos of the little skate, Raja erinacea , ranging in age from 27 to 144 days after spawning. Circulation starts at the end of the first month. At that time, the heart is S-shaped...