دانلود مقاله ISI انگلیسی شماره 77150
ترجمه فارسی عنوان مقاله

تغییرات فصلی در شبانه روزی ریتم پلاسما ملاتونین در مارکمولک های رو به نابودی

عنوان انگلیسی
Seasonal Variations in Circadian Rhythms of Plasma Melatonin in Ruin Lizards
کد مقاله سال انتشار تعداد صفحات مقاله انگلیسی
77150 2002 6 صفحه PDF
منبع

Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)

Journal : Hormones and Behavior, Volume 41, Issue 4, June 2002, Pages 414–419

ترجمه کلمات کلیدی
ملاتونین؛ صنوبری؛ ریتم شبانه روزی؛ مارمولک؛ فصلی
کلمات کلیدی انگلیسی
melatonin; pineal; circadian rhythms; lizards; seasonality
پیش نمایش مقاله
پیش نمایش مقاله  تغییرات فصلی در شبانه روزی ریتم پلاسما ملاتونین در مارکمولک های رو به نابودی

چکیده انگلیسی

We examined melatonin profiles of ruin lizards in different seasons (spring, summer, and autumn) under light:dark (LD) and concomitant responses when transferred to continuous darkness (DD) to determine the degree to which previously reported seasonally dependent effects of pinealectomy on locomotor behavior are related to melatonin secretion. The amplitude of the melatonin rhythm and the amount of melatonin produced over 24 h varied with season. In spring, the amount of melatonin produced was greatest and the amplitude 4– 5 times that found in summer or autumn. The degree of self-sustainment of the melatonin rhythm when transferred to DD also varied with season. In DD, melatonin levels remained high but did not exhibit circadian variation in spring. In summer, the melatonin profile persisted virtually unchanged in DD, showing the existence of a circadian rhythm. Finally, in the fall there was no circadian variation in DD and levels remained low. These responses correspond closely to previously reported effects of pinealectomy on locomotor behavior where there is little or no effect of pinealectomy in spring or fall but a profound alteration of locomotor behavior in summer. These results suggest that the seasonally dependent effects of pinealectomy on locomotor behavior in ruin lizards are related to a seasonally mediated change in the degree of self-sustainment of some component of the circadian pace-making system of which melatonin plays some role.