PT  - JOURNAL ARTICLE
AU  - Morisawa, M
AU  - Suzuki, K
TI  - Osmolality and potassium ion: their roles in initiation of sperm motility in teleosts
AID  - 10.1126/science.7444445
DP  - 1980 Dec 05
TA  - Science
PG  - 1145--1147
VI  - 210
IP  - 4474
4099  - http://science.sciencemag.org/content/210/4474/1145.short
4100  - http://science.sciencemag.org/content/210/4474/1145.full
SO  - Science1980 Dec 05; 210
AB  - Spermatozoa that are quiescent in electrolyte and nonelectrolyte solutions isotonic to seminal plasma show motility when the semen is diluted with hypotonic solution in freshwater teleosts (four species tested) and with hypertonic solution in marine teleosts (five species tested). Decrease or increase, respectively, in osmolality of the environment may be the factor initiating sperm motility in these species. The motility of chum salmon spermatozoa in a sodium chloride solution isotonic to seminal plasma is completely suppressed by approximately 10 millimoles of potassium per kilogram; topminnow spermatozoa, however, were immotile in a nonelectrolyte solution, and motility was induced by electrolytes, especially potassium. Thus ions, rather than osmolality, may be an essential determinant of sperm motility in salmonid and viviparous teleosts.