In vitro effects of beta-carotene for the motility, ATP, and intracellular free Ca(2+) concentrations of fowl spermatozoa.
The motility of intact fowl spermatozoa was vigorous at 25 degrees C, but decreased gradually following the addition of 0-100 microM beta-carotene in a dose-dependent manner. Even in the presence of stimulators of fowl sperm motility, such as Ca(2+) or calyculin A, the motility of intact spermatozoa at both 25 and 40 degrees C remained inhibited following the addition of beta-carotene. Under all of these circumstances, sperm ATP concentrations were not reduced by the addition of beta-carotene. Moreover, the motility of demembranated spermatozoa was not inhibited by the addition of the same concentrations of beta-carotene. No changes in intracellular free Ca(2+) concentrations, measured by means of a fluorescent Ca(2+) indicator, fura-2, were observed in intact beta-carotene -treated spermatozoa. These results suggest that beta-carotene is involved in the inhibition of the flagellar movement of fowl spermatozoa without change in energy production, and that the target of beta-carotene might be present in the cytoplasmic matrix and/or the plasma membrane, but not retained in the axoneme and/or accessory cytoskeletal components.
Ashizawa
K
K
Laboratory of Animal Reproduction, Faculty of Agriculture, Miyazaki University, Miyazaki, Japan. a0c303u@cc.miyazaki-u.ac.jp
Tomita
Y
Y
Kanemaru
C
C
Tsuzuki
Y
Y
D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D002118:Calcium / Q000378:metabolism; D007424:Intracellular Fluid / Q000378:metabolism; D008297:Male; D011200:Poultry; D013081:Sperm Motility / Q000187:drug effects*; D013094:Spermatozoa / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology; D019207:beta Carotene / Q000494:pharmacology*
D000975:Antioxidants; D019207:beta Carotene; D000255:Adenosine Triphosphate; D002118:Calcium