Linden H, del Rio Garcia J, Huber A, Kreil G, Smyth D
National Institute for Medical Research, Mill Hill, London, UK.
FEBS Lett. 1996 Jan 22;379(1):11-4. doi: 10.1016/0014-5793(95)01468-3.
Human seminal fluid contains a number of tripeptide amides with similar structures to thyrotropin releasing hormone (TRH), two of which have been identified as pGlu-Glu-Pro amide and pGlu-Phe-Pro amide. To determine whether these peptides originate in the same tissues and have the same molecular origin, TRH-immunoreactive peptides were extracted from the prostate and testis of the rabbit, purified by ion exchange chromatography and HPLC, and identified by co-chromatography with 3H-labelled marker peptides. In addition, trypsin digestion was used to release TRH-like tripeptides from N-extended forms of these peptides. The sole TRH-like peptide in the prostate was shown to be pGlu-Glu-Pro amide; it was not accompanied by a detectable amount of pGlu-Phe-Pro amide. The prostate also appeared to contain a very small amount of N-extended forms of these peptides. In contrast to the prostate, the testis contained high concentrations of N-extended forms of pGlu-Phe-Pro amide but essentially no tripeptide. The testis also contained N-extended forms of two other neutral TRH-like peptides which were less hydrophobic than pGlu-Phe-Pro amide. Neither the prostate nor the testis contained a significant amount of TRH. The results show that in the rabbit the TRH-like peptides pGlu-Glu-Pro amide and pGlu-Phe-Pro amide occur in different tissues and appear to be formed from different precursors.
人类精液中含有多种与促甲状腺激素释放激素（TRH）结构相似的三肽酰胺，其中两种已被鉴定为焦谷氨酸 - 谷氨酸 - 脯氨酸酰胺和焦谷氨酸 - 苯丙氨酸 - 脯氨酸酰胺。为了确定这些肽是否起源于相同组织且具有相同的分子起源，从兔子的前列腺和睾丸中提取TRH免疫反应性肽，通过离子交换色谱和高效液相色谱进行纯化，并通过与3H标记的标记肽共色谱法进行鉴定。此外，使用胰蛋白酶消化从这些肽的N端延伸形式中释放出TRH样三肽。前列腺中唯一的TRH样肽被证明是焦谷氨酸 - 谷氨酸 - 脯氨酸酰胺；未检测到可检测量的焦谷氨酸 - 苯丙氨酸 - 脯氨酸酰胺。前列腺似乎还含有极少量的这些肽的N端延伸形式。与前列腺相反，睾丸中含有高浓度的焦谷氨酸 - 苯丙氨酸 - 脯氨酸酰胺的N端延伸形式，但基本上不含三肽。睾丸中还含有另外两种中性TRH样肽的N端延伸形式，它们的疏水性比焦谷氨酸 - 苯丙氨酸 - 脯氨酸酰胺低。前列腺和睾丸中均未含有大量的TRH。结果表明，在兔子中，TRH样肽焦谷氨酸 - 谷氨酸 - 脯氨酸酰胺和焦谷氨酸 - 苯丙氨酸 - 脯氨酸酰胺存在于不同组织中，且似乎由不同的前体形成。
