Yuwiler A, Klein D C, Buda M, Weller J L
Am J Physiol. 1977 Sep;233(3):E141-6. doi: 10.1152/ajpendo.1977.233.3.E141.
The activity of pineal N-acetyltransferase in the neonatal rat does not exhibit the large daily rhythm seen in the adult and is intermediate between the low day and high night adult values. These intermediate values appear to result from adrenergic stimulation. Blockade of adrenergic receptors or of catecholamine synthesis results in a decrease in enzyme activity in vivo. In vitro studies provide additional evidence of a completely developed postsynaptic adrenergic control system for pineal N-acetyltransferase activity at birth. Our observations indicate that the appearance of a circadian rhythm in pineal N-acetyltransferase at the end of the first week of life reflects the development of presynaptic mechanisms and structures necessary for the control of catecholamine release and uptake. These events follow the developmental appearance of the postsynaptic mechanisms required to mediate the adrenergic-cycle AMP regulation of pineal N-acetyltransferase activity, which can be detected prior to birth.
新生大鼠松果体N - 乙酰基转移酶的活性并不呈现出成体中所见的大幅度日节律，而是介于成体白天的低水平值和夜间的高水平值之间。这些中间值似乎是由肾上腺素能刺激导致的。肾上腺素能受体阻断或儿茶酚胺合成阻断会导致体内酶活性降低。体外研究进一步证明，出生时松果体N - 乙酰基转移酶活性存在一个完全发育的突触后肾上腺素能控制系统。我们的观察表明，出生后第一周结束时，松果体N - 乙酰基转移酶昼夜节律的出现反映了控制儿茶酚胺释放和摄取所需的突触前机制和结构的发育。这些事件发生在介导松果体N - 乙酰基转移酶活性的肾上腺素能 - 环磷酸腺苷调节所需的突触后机制出现之后，而这种突触后机制在出生前就能检测到。
