Valases C, Wright S J, Catravas G N
Exp Brain Res. 1980;40(3):261-4. doi: 10.1007/BF00237790.
The concentrations of cAMP and cGMP in the rat hypothalamus varied considerably over a 24-h period. The cAMP levels were found to be relatively higher in the morning and lower during the afternoon and night. Cyclic GMP levels reached highest values during the period of darkness and were lowest during the day. Deprivation of food did not have any appreciable effect on the pattern of these changes.
大鼠下丘脑内的环磷酸腺苷（cAMP）和环磷酸鸟苷（cGMP）浓度在24小时内变化显著。发现cAMP水平在早晨相对较高，而在下午和夜间较低。环磷酸鸟苷水平在黑暗期间达到最高值，在白天则最低。禁食对这些变化模式没有任何明显影响。
