International Journal of Biometeorology

, Volume 32, Issue 2, pp 103–107

Melatonin and 6-methoxy-2-benzoxazolinone (6-MBOA) alter the response of the male Syrian hamster to natural photoperiod

  • M. K. Vaughan
  • J. C. Little
  • D. C. Powell
  • M. Puig-Domingo
  • R. J. Reiter
Original Articles

Abstract

Adult male hamsters bearing either a blank beeswax, 6-methoxy-2-benzoxazolinone (6-MBOA), or melatonin pellet were exposed to 8 weeks (Oct. 6–Dec. 6) of natural autumn decreasing photoperiod (<11 h light) and temperature conditions (mean 10°C for last 4 weeks) or to a 14 h light/10 h dark (14L∶10D) photoperiod and controlled temperature (20°C). Melatonin but not 6-MBOA pellets partially prevented the combined effects of short photoperiod and cold temperatures on the testes and accessory organs. However, both 6-MBOA-and melatonin-treated hamsters maintained outdoors had significantly higher pituitary follicle stimulating hormone (FSH) values compared to their respective indoor-treated controls or to the animals kept outdoors and treated with a blank beeswax pellet. When one compares the various effects of 6-MBOA and melatonin (2 mg/month) on the reproductive system of the male hamster, 6-MBOA is not as effective as melatonin in altering reproductive responses to short photoperiod and cool temperatures at the dose administered.

Key words

6-Methoxy-2-benzoxazolinone 6-MBOA Melatonin Hamster Natural photoperiod 

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Copyright information

© International Society of Biometeorology 1988

Authors and Affiliations

  • M. K. Vaughan
    • 1
  • J. C. Little
    • 2
  • D. C. Powell
    • 2
  • M. Puig-Domingo
    • 1
  • R. J. Reiter
    • 1
  1. 1.Department of Cellular and Structural BiologyThe University of Texas Health Science Center at San AntonioSan AntonioUSA
  2. 2.Department of BiologyAbilene Christian UniversityAbileneUSA

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