Abstract
Three-spined stickleback Gasterosteus aculeatus, males were implanted with Silastic capsules filled with different aromatase inhibitors; 1,4,6-androstatriene-3,17-dione or the non-steroidal CGS16949 A, 4-(5,6,7,8-tetrahydrimidazol [1,5-a]pyridin-5-yl) benzonitrile monohydrochloride or empty capsules. The fish were then exposed to long or short photoperiod. Under the long photoperiod most fish in all treatments displayed a hypertrophied kidney (a secondary sexual character in sticklebacks) and completed, quiescent spermatogenesis, similar as in the natural spawning period. Under the short photoperiod the controls had unstimulated kidneys and an active spermatogenesis, whereas the males implanted with both aromatase inhibitors had stimulated kidneys, though not to the extent as in the long photoperiod, and completed, quiescent spermatogenesis. These findings suggest that aromatization is of importance for the inhibitory effects of short photoperiod on reproduction in the stickleback.
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Andersson, E., Bogerd, J., Borg, B., Sharp, P.J., Sherwood, N.M. and Goos, H.J.Th. 1995. Characterization and localization of gonadotropin-releasing hormone in the brain and pituitary of the three-spined stickleback, Gasterosteus aculeatus. Cell Tiss. Res. 279: 485–493.
Andersson, E., Mayer, I. and Borg, B. 1988. Inhibitory effect of 11-ketoandrostenedione and androstenedione on spermato-genesis in the three-spined stickleback, Gasterosteus aculea-tus. L. J. Fish Biol. 33: 835–840.
Antonopoulou, E., Mayer, I., Berglund, I. and Borg, B. 1995. Effects of aromatase inhibitors on sexual maturation in Atlan-tic salmon, Salmo salar male parr. Fish Physiol. Biochem. 14: 15–24.
Baggerman, B. 1957. An experimental study on the timing of breeding and migration in the three-spined stickleback (Gasterosteus aculeatus L.). Arch. Néerl. Zool. 12: 105–317.
Borg, B. 1981. Effects of methyltestosterone on spermatogenesis and secondary sexual characters in the three-spined stickle-back (Gasterosteus aculeatus L.). Gen. Comp. Endocrinol. 44: 177–180.
Borg, B. 1982. Seasonal effects of photoperiod and temperature on spermatogenesis and secondary sexual characters in the three-spined stickleback (Gasterosteus aculeatus L.). Can. J. Zool. 60: 3377–3386.
Borg, B. 1994. Androgens in teleost fishes. Comp. Biochem. Physiol. 109C: 219–245.
Borg, B., Andersson, E., Mayer, I., Zandbergen, M.A. and Peute, J. 1989a. Effects of gonadectomy on pituitary gonadotropic cells of the three-spined stickleback. Gasterosteus aculeatus L., under long photoperiod in winter: Indications for a posi-tive feedback. Gen. Comp. Endocrinol. 76: 12–18.
Borg, B., Antonopoulou, E., Andersson, E., Carlberg, T. and Mayer, I. 1993. Effectiveness of several androgens in stimu-lating kidney hypertrophy, a secondary sexual character, in castrated male three-spined sticklebacks, Gasterosteus acu-leatus. Can. J. Zool. 71: 2327–2329.
Borg, B., Mayer, I., Lambert, J.G.D., Granneman, J. and Schulz, R. 1992. Metabolism of androstenedione and 11-ketotestos-terone in the kidney of the three-spined stickleback, Gaster-osteus aculeatus. Gen. Comp. Endocrinol. 86: 248–256.
Borg, B., Peute, J., Reschke, M. and van den Hurk, R. 1987a. Effects of photoperiod and temperature on testes, renal epi-thelium, and pituitary gonadotropic cells of the three-spined stickleback, Gasterosteus aculeatus L. Can. J. Zool. 65: 14–19.
Borg, B., Schoonen, W.G.E.J. and Lambert, J.G.D. 1989b. Ster-oid metabolism in the testes of the breeding and nonbreeding three-spined stickleback, Gasterosteus aculeatus. Gen. Comp. Endocrinol. 73: 40–45.
Borg, B., Timmers, R.J.M. and Lambert, J.G.D. 1987b. Aromatase activity in the brain of the three-spined stickle-back, Gasterosteus aculeatus. I. Distribution and effects of season and photoperiod. Exp. Biol. 47: 63–68.
Borg, B., Timmers, R.J.M. and Lambert, J.G.D. 1987c. Aromatase activity in the brain of the three-spined stickleback, Gasterosteus aculeatus. II. Effects of castration in winter. Exp. Biol. 47: 69–71.
Callard, G.V., Petro, Z. and Ryan, K.J. 1981. Estrogen synthesis in vitro and in vivo in the brain of the marine teleost (Myoxo-cephalus). Gen. Comp. Endocrinol. 29: 14–20.
Crim, L.W., Peter, R.E. and Billard, R. 1981. Onset of gonado-tropic hormone accumulation in the immature trout pituitary gland in response to estrogen or aromatizable androgen ster-oid hormones. Gen. Comp. Endocrinol. 44: 374–381.
de Leeuw, R., Wurth, Y.A., Zandbergen, M.A., Peute, J. and Goos, H.J.Th. 1986. The effects of aromatizable androgens, non-aromatizable androgens, and estrogens on gonadotropin release in castrated African catfish, Clarias gariepinus (Burchell). Cell Tiss. Res. 243: 587–594.
Mayer, I., Borg, B. and Schulz, R. 1990. Seasonal changes in and effect of castration/androgen replacement on the plasma lev-els of five androgens in the male three-spined stickleback, Gasterosteus aculeatus L. Gen. Comp. Endocrinol. 79: 23–30.
Wozniak, A., Holman, S.D. and Hutchison, J.B. 1992. In vitro potency and selectivity of the non-steroidal androgen aromatase inhibitor CGS 16949A compared to steroidal inhibitors in the brain. J. Steroid. Biochem. Molec. Biol. 43: 281–287.
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Bornestaf, C., Antonopoulou, E., Mayer, I. et al. Effects of aromatase inhibitors on reproduction in male three-spined sticklebacks, Gasterosteus aculeatus, exposed to long and short photoperiods. Fish Physiology and Biochemistry 16, 419–423 (1997). https://doi.org/10.1023/A:1007776517447
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DOI: https://doi.org/10.1023/A:1007776517447