Walter R, Audhya T K, Schlesinger D H, Shin S, Saito S, Sachs H
Endocrinology. 1977 Jan;100(1):162-74. doi: 10.1210/endo-100-1-162.
Neurophysin (Np) is generally found in close association with vasopressin and oxytocin in the hypothalamo-neurohypophyseal complex. Dog neurophysin I and II have been isolated from fresh and frozen posterior pituitaries. The proteins were characterized on the basis of disc electrophoresis, immunological properties, amino acid composition and partial sequence determination. The amino terminal sequence of dog Np I is Ala-Ala-Leu-Asp-Leu-Asp-Val-Arg-Gln-Cys-Leu-Pro-Cys-Gly-Pro-Gly-Gly-Gln-Gly-while that of dog Np-II is Ala-Met-Ser-Asp-Leu-Glu-Leu. The dog Np I appears to be metabolically less stable than Np II. Isotope experiments with [35S]cystine or 3H-labeled amino acids using a design of "in vitro pulse and in vitro chase" as well as "in vivo pulse and in vivo chase," added further confirmation of the capability of the hypothalamic neurosecretory cells to synthesize concomitantly precursors of Np and vasopressin. The radioactively labeled precursors were converted to Np-like protein and vasopressin, both of which were isolated.
神经垂体素（Np）通常在下丘脑 - 神经垂体复合体中与血管加压素和催产素紧密相关。犬神经垂体素I和II已从新鲜和冷冻的垂体后叶中分离出来。基于圆盘电泳、免疫特性、氨基酸组成和部分序列测定对这些蛋白质进行了表征。犬Np I的氨基末端序列是Ala - Ala - Leu - Asp - Leu - Asp - Val - Arg - Gln - Cys - Leu - Pro - Cys - Gly - Pro - Gly - Gly - Gln - Gly，而犬Np - II的氨基末端序列是Ala - Met - Ser - Asp - Leu - Glu - Leu。犬Np I在代谢上似乎比Np II更不稳定。使用“体外脉冲和体外追踪”以及“体内脉冲和体内追踪”的设计，用[35S]胱氨酸或3H标记的氨基酸进行的同位素实验，进一步证实了下丘脑神经分泌细胞同时合成Np和血管加压素前体的能力。放射性标记的前体被转化为类似Np的蛋白质和血管加压素，二者均被分离出来。
