Török J, Kristek F
Ustavu normálnej a patologickej fyziológie CFV SAV v Bratislave.
Bratisl Lek Listy. 1990 Mar;91(3):177-84.
Contractions induced by transmural nervous stimulation were studied on isolated preparations of the portal vein of newborn and adult guinea pigs and the walls of the studied vessels were examined by electron microscopy. Transmural nervous stimulation elicited contractions of the portal vein in all developmental types yet with a higher threshold frequency for inducing contractions in fetuses than in newborn animals. Guanethidine and phentolamine reduced while cocaine enhanced the neurogenic contractions, indicating their adrenergic nature. Electron microscopic studies revealed uncompleted differentiation of the tunica media of the fetal portal vein into the inner circular and outer longitudinal layer. The region of the adventitio-medial border locates the external nervous plexus from which already in the fetus nerve fibers penetrate between the longitudinal and circular layer of the tunica media to constitute there inner nervous plexus. The vesicles in the nerve endings displayed the same characteristics in all the developmental types studied. The obtained results indicate a high degree of morphological and functional maturation of the adrenergic regulation of the portal vein already in the fetus at the end of the prenatal period in guinea pigs. (Fig. 9, Ref. 16.)
在新生豚鼠和成年豚鼠门静脉的离体标本上研究了经壁神经刺激诱导的收缩，并通过电子显微镜检查了所研究血管的壁。经壁神经刺激在所有发育类型中均引起门静脉收缩，但与新生动物相比，胎儿诱导收缩的阈值频率更高。胍乙啶和酚妥拉明可降低神经源性收缩，而可卡因可增强神经源性收缩，表明它们具有肾上腺素能性质。电子显微镜研究显示，胎儿门静脉中膜未完全分化为内环层和外纵层。外膜-中膜边界区域有外部神经丛，在胎儿期神经纤维就已从中穿过，在中膜的纵层和环层之间形成内部神经丛。在所研究的所有发育类型中，神经末梢中的囊泡都表现出相同的特征。所得结果表明，在豚鼠产前期末期，胎儿门静脉的肾上腺素能调节在形态和功能上已高度成熟。（图9，参考文献16）
