Van de Heijning B J, Maigret C, Koekkoek-van den Herik I, Smelik W F, van Wimersma Greidanus T B
Rudolf Magnus Institute, Department of Pharmacology, Utrecht, The Netherlands.
Neuropeptides. 1994 Jun;26(6):371-8. doi: 10.1016/0143-4179(94)90021-3.
The effects on vasopressin (VP) release of three dynorphin-A fragments and two antidynorphin antisera were tested in vivo and in vitro. In vivo, the order of potency to inhibit VP release 30 min upon i.c.v. injection was: dynorphin-A-(1-17) > dynorphin-A-(1-13) > dynorphin-A-(1-8). l.c.v. co-administration of 10 nmoles of the specific endopeptidase-inhibitor cFPAAF-pAB and dynorphin-A-(1-8) also suppressed VP secretion. Dynorphin-A-(1-17) antiserum enhanced VP release 20 and 60 min after i.c.v. injection. The antiserum that recognized dynorphin-A-(1-13) elevated VP plasma levels at 60 min post-injection. In vitro, dynorphin-A-(1-8) suppressed electrically evoked VP release from the isolated neural lobe. VP release was not affected by dynorphin-A-(1-13), dynorphin-A-(1-17), naloxone, or by the anti-dynorphin antisera. These data indicate that dynorphin-A-(1-17), rather than dynorphin-A-(1-8), plays a role in the centrally located control of neurohypophysial VP release, whereas dynorphin-A-(1-8) is involved in the control located in the posterior pituitary. The synthetic intermediate fragment dynorphin-A-(1-13) appears to affect VP release both centrally and peripherally.
在体内和体外测试了三种强啡肽A片段和两种抗强啡肽抗血清对血管加压素（VP）释放的影响。在体内，脑室内注射后30分钟抑制VP释放的效力顺序为：强啡肽A-（1-17）＞强啡肽A-（1-13）＞强啡肽A-（1-8）。脑室内共同给予10纳摩尔的特异性内肽酶抑制剂cFPAAF-pAB和强啡肽A-（1-8）也能抑制VP分泌。强啡肽A-（1-17）抗血清在脑室内注射后20分钟和60分钟增强VP释放。识别强啡肽A-（1-13）的抗血清在注射后60分钟升高VP血浆水平。在体外，强啡肽A-（1-8）抑制从分离的神经叶电诱发的VP释放。VP释放不受强啡肽A-（1-13）、强啡肽A-（1-17）、纳洛酮或抗强啡肽抗血清的影响。这些数据表明，在神经垂体VP释放的中枢控制中起作用的是强啡肽A-（1-17），而不是强啡肽A-（1-8），而强啡肽A-（1-8）参与垂体后叶的控制。合成的中间片段强啡肽A-（1-13）似乎在中枢和外周都影响VP释放。
