Hoffman R A, Johnson L B
J Pineal Res. 1985;2(3):209-15. doi: 10.1111/j.1600-079x.1985.tb00641.x.
Four-week-old male hamsters, born and raised in total darkness or in LD 14:10 (hr) were exposed to several low levels of illumination for 14 weeks. Analyses showed that testicular weights were significantly affected by both photic history and illuminance levels. Animals born in the dark possessed larger testes than those born in LD cycles and, further, displayed less responsiveness to levels of illumination below those required to suppress pineal function. While gonadal responses to photic duration may be said to be "all or none," those resulting from insufficient illuminance levels are seemingly graded. Thus, the pineal gland may act indirectly as a photodosimeter at low illuminance levels.
四周龄的雄性仓鼠，出生并饲养在完全黑暗或14小时光照：10小时黑暗（LD 14:10）的环境中，之后暴露于几种低光照水平下14周。分析表明，睾丸重量受到光照历史和光照强度水平的显著影响。在黑暗中出生的动物睾丸比在光暗循环中出生的动物更大，而且，对于低于抑制松果体功能所需光照水平的光照强度变化，前者的反应性更低。虽然性腺对光照时长的反应可说是“全或无”，但光照强度不足所导致的反应似乎是分级的。因此，在低光照强度水平下，松果体可能间接起到光剂量计的作用。
