Deguchi T
J Neurochem. 1982 Mar;38(3):797-802. doi: 10.1111/j.1471-4159.1982.tb08700.x.
The circadian rhythms of serotonin N-acetyltransferase activity in the pineal glands of infant and adult rats were compared. The nighttime increase of N-acetyltransferase activity in the pineals of infant rats was blocked by removal of superior cervical ganglion or by pretreatment with reserpine, l-propranolol, and cycloheximide. Injection of isoproterenol to infant rats markedly elevated pineal N-acetyltransferase activity. When the pineal glands of infant rats were organ-cultured, N-acetyltransferase activity spontaneously increased 7--12 h after the rats were killed. When infant rats were previously denervated or pretreated with reserpine and their pineals were cultured, this spontaneous elevation of N-acetyltransferase activity was abolished, indicating that the transient increase of the enzyme activity in organ culture was due to a liberation of catecholamine from degenerating nerve endings. Additional illumination until midnight prevented the nighttime increase of N-acetyltransferase activity in intact infant rats but not in blinded infant rats. These observations are taken to indicate that N-acetyltransferase rhythm in immature rat pineals is regulated by the sympathetic nerves in the same manner as in adult rat pineals, that the immature rat pineal does not contain a time-keeping system, and that there is no extraretinal light perception in infant rats as far as N-acetyltransferase rhythm is concerned.
比较了幼年和成年大鼠松果体中血清素N - 乙酰转移酶活性的昼夜节律。切除颈上神经节或用利血平、L - 普萘洛尔和环己酰亚胺预处理可阻断幼年大鼠松果体中N - 乙酰转移酶活性的夜间升高。给幼年大鼠注射异丙肾上腺素可显著提高松果体N - 乙酰转移酶活性。当幼年大鼠的松果体进行器官培养时，在大鼠处死7 - 12小时后，N - 乙酰转移酶活性会自发增加。当幼年大鼠先前已去神经支配或用利血平预处理后再培养其松果体时，这种N - 乙酰转移酶活性的自发升高就会消失，这表明器官培养中酶活性的短暂增加是由于去神经末梢释放儿茶酚胺所致。持续光照至午夜可阻止完整幼年大鼠松果体中N - 乙酰转移酶活性的夜间升高，但对失明幼年大鼠则无此作用。这些观察结果表明，未成熟大鼠松果体中的N - 乙酰转移酶节律与成年大鼠松果体一样，受交感神经调节；未成熟大鼠松果体不含计时系统；就N - 乙酰转移酶节律而言，幼年大鼠不存在视网膜外光感知。
