Panova I G, Sologub A A, Burlakova O V, Stroeva O G
Ontogenez. 1993 Mar-Apr;24(2):49-54.
The activity of melanotropins in pituitary homogenates and blood of Wistar rats obtained from the nursery Stolbovaia (Russian Academy of Medical Sciences) was studied using the method of biological testing (Hogben, Slome, 1931; Golichenkov, 1980). In order to elucidate, to what extent the normal status of melanotropic activity is retained in albino rats, two experimental series were performed. Melanotropic activity was determined in (1) intact rats and (2) in rats receiving subcutaneous injections of parachlorophenylalanine, a specific inhibitor of serotonin synthesis. Melanotropic activity of Wistar rats hypophysis during the studied period of development was similar to that of normal pigmented rats. However, the peak of melanotropic activity of blood which is characteristically observed in pigmented rats on day 3 of postnatal development is absent in the case of Wistar rats. The experimentally induced decrease in the serotonin level did not result in the increased melanotropic activity of blood. These data suggest that certain structures of hypophysis responsible for MSH secretion can be disturbed in Wistar rats. A short-term peak of blood MSH in rats during the first week after birth is known to provide for maturation of dopaminergic neurons located in the arcuate nucleus of the hypothalamus. Consequently, the absence of such peak in Wistar rats should result in neuroendocrine disturbances such as inadequate functioning of dopaminergic neurons responsible for melanotropin secretion by hypophysis beginning from the second week after birth (Lichtensteiger, Schlumpf, 1986).
采用生物检测法（霍格本、斯洛姆，1931年；戈利琴科夫，1980年），对从俄罗斯医学科学院斯托尔博瓦亚繁殖场获取的Wistar大鼠垂体匀浆和血液中促黑素的活性进行了研究。为了阐明白化大鼠的促黑素活性正常状态在多大程度上得以保留，进行了两个实验系列。在（1）完整大鼠和（2）皮下注射对氯苯丙氨酸（一种血清素合成的特异性抑制剂）的大鼠中测定促黑素活性。在研究的发育阶段，Wistar大鼠垂体的促黑素活性与正常有色大鼠相似。然而，在出生后第3天有色大鼠血液中促黑素活性出现的特征性峰值在Wistar大鼠中并未出现。实验诱导的血清素水平降低并未导致血液中促黑素活性增加。这些数据表明，Wistar大鼠中负责促黑素分泌的垂体某些结构可能受到了干扰。已知出生后第一周大鼠血液中促黑素的短期峰值可促进位于下丘脑弓状核的多巴胺能神经元成熟。因此，Wistar大鼠中不存在这样的峰值应会导致神经内分泌紊乱，例如从出生后第二周开始，负责垂体促黑素分泌的多巴胺能神经元功能不足（利希滕施泰格、施伦普夫，1986年）。
