Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.13/804286
- Simultaneous measurement of intracellular nitric oxide and free calcium levels in chordate eggs demonstrates that nitric oxide has no role at fertilization
Hyslop, Louise A.;
Nixon, Victoria L.;
Jones, Keith T.
- At fertilization in sea urchin, the free radical nitric oxide (NO) has recently been suggested to cause the intracellular Ca²⁺ rise responsible for egg activation. The authors suggested that NO could be a universal activator of eggs and the present study was set up to test this hypothesis. Intracellular NO and Ca²⁺ levels were monitored simultaneously in eggs of the mouse or the urochordate ascidian Ascidiella aspersa. Eggs were either fertilized or sperm extracts microinjected. Sperm-induced Ca²⁺ rises were not associated with any global, or local, change in intracellular NO, although we were able to detect NO produced by the addition of a NO donor. Furthermore, the NO synthase inhibitor NG-nitro-image-arginine methyl ester had no effect on sperm-induced Ca²⁺ release but did block completely ionomycin-induced NO synthase activation. Therefore, we suggest that the current data provide evidence that NO has no role in the fertilization of these two chordate eggs.
- Developmental Biology Vol. 234, Issue 1, p. 216-230
- Publisher Link
- Academic Press
- Resource Type
- journal article