What does a common channel for electrolytes and non-electrolytes in the sperm mean?

Cell volume is central to osmoregulation in intact cells. Bovine spermatozo a, as also other mammalian spermatozoa, exhibit a very rapid regulatory vol ume decrease (RVD) when exposed to hypotonic saline media. This response, f astest known in animal cells, is mediated by a putative potassium channel w hich the pharmacological properties of a conventional channel and yet admit s both electrolytes and non-electrolytes. The evolutionary basis and functi onal role of this conserved quinine-sensitive channel in mammalian sperm co uld offer hitherto unexplored facets of the link(s) between ecology and rep roduction. (C) 2000 Academic Press.