Rotiroti D, Germanà G, Nisticò G, Melchiorri P, Erspamer V
Gen Comp Endocrinol. 1984 Oct;56(1):24-31. doi: 10.1016/0016-6480(84)90057-1.
The effects of dermorphin, a new potent opioid peptide, on structural and ultrastructural changes in the crop sac and in pituitary lactotrophs were assessed in pigeons (Columba livia). A single administration of dermorphin into the third cerebral ventricle (1 microgram) and the same dose repeated for 3 consecutive days both produced maximal crop sac stimulation, as documented by the presence of milk-like material as well as by scanning and transmission electron microscopy of crop sac mucosa. In addition, marked stimulatory effects were also observed in pituitary lactotrophs, as shown by stimulation of Golgi apparatus, enlargement of rough endoplasmic reticulum, increase in mitochondria size, and the presence of lysosomes and electron-opaque granules. The stimulatory effects of dermorphin on the crop sac and lactotrophs were completely prevented by naloxone, an antagonist at opiate receptors. Since dermorphin is a natural constituent of the avian brain, it has been suggested that this peptide may represent the still-obscure hypothalamic prolactin stimulatory factor.
在鸽子（家鸽）身上评估了一种新型强效阿片肽——皮啡肽对嗉囊和垂体催乳细胞结构及超微结构变化的影响。向第三脑室单次注射皮啡肽（1微克）以及连续3天重复注射相同剂量，均产生了最大程度的嗉囊刺激，这通过出现乳状物质以及对嗉囊黏膜进行扫描和透射电子显微镜观察得以证实。此外，在垂体催乳细胞中也观察到了明显的刺激作用，表现为高尔基体受到刺激、粗面内质网扩大、线粒体尺寸增加以及存在溶酶体和电子致密颗粒。阿片受体拮抗剂纳洛酮完全阻断了皮啡肽对嗉囊和催乳细胞的刺激作用。由于皮啡肽是鸟类大脑的天然成分，有人提出这种肽可能代表了仍不清楚的下丘脑催乳素刺激因子。
