In vitro contraction of the canine corpus cavernosum penis by direct perfusion with prolactin or growth hormone.
In vitro contraction of the canine corpus cavernosum penis by direct perfusion with prolactin or growth hormone.
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DOI：
10.1016/s0022-5347(01)65918-4
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发表时间：
1996-08
期刊：
影响因子：
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通讯作者：
Shibun Ra;Hikaru Aoki;Tomoaki Fujioka;Fumio Sato;Takashi Kubo;Naoki Yasuda
中科院分区：
文献类型：
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作者：
Shibun Ra;Hikaru Aoki;Tomoaki Fujioka;Fumio Sato;Takashi Kubo;Naoki Yasuda
目的众所周知，高泌乳素血症（最常见于泌乳素瘤患者）会导致性腺功能减退和阳痿。高催乳素血症似乎很可能导致阳痿，至少部分是通过催乳素（PRL）的某些内在特性，而不是通过其对下丘脑-垂体-性腺睾酮动态的抑制作用。在本研究中，我们使用体外犬模型来试图阐明PRL对阴茎海绵体的直接作用是否可能导致勃起功能不全。还研究了与 PRL 具有密切结构和功能同源性的生长激素 (GH) 和胎盘催乳素 (PL)。 材料和方法在灌注介质中存在或不存在 10sup -5 至 10sup -9 M. PRL、GH 或 PL 的情况下，用海绵体条进行等长张力测量。测试物质引起的张力变化相对于 120 mEq KCl 引起的张力变化进行标准化。结果 PRL 和 GH 均产生与剂量相关的海绵体张力升高（p 小于 0.01），而可比较剂量的 PL 和硫醇裂解的 PRL 则没有影响（p 大于 0.05）。当120 mEq KCl产生的张力上升为100%时，PRL和GH产生的最大收缩分别为80%和110%。对于PRL和GH来说，最低有效浓度为10sup -8 至10sup -7 M。用吲哚美辛（10 sp -5 M.）而非河鲀毒素（10 sp -5 M.）预处理，部分抑制（p小于0.05）PRL的作用。结论这些结果表明，PRL和GH直接且特异性地产生阴茎海绵体收缩，导致勃起功能不全，并且PRL的作用部分由前列腺素介导。
PurposeIt is well established that hyperprolactinemia, most typically seen in prolactinoma patients, causes hypogonadism and impotence. There seem to be a good possibility that hyperprolactinemia causes impotence, at least partially via some intrinsic property of prolactin (PRL), rather than through its suppressive effects on the hypothalamic-pituitary-gonadal testosterone dynamics. In the present investigation, we used an in vitro canine model to attempt to clarify whether direct action of PRL on the corpus cavernosum penis may lead to erectile insufficiency. Growth hormone (GH) and placental lactogen (PL), both having close structural and functional homologies to PRL, were also studied.Materials and MethodsIsometric tension measurement with cavernous strips was performed in the presence or absence of 10 sup -5 to 10 sup -9 M. PRL, GH, or PL in the perfusion medium. The tension change induced by the test substances was normalized relative to that induced by 120 mEq KCl.ResultsBoth PRL and GH produced dose-related elevations (p less than 0.01) of the cavernous tension, whereas PL and thiol-cleaved PRL in comparable doses were without effect (p greater than 0.05). When the tension rise produced by 120 mEq KCl was taken as 100 percent, the maximum contractions produced by PRL and GH were 80 percent and 110 percent. The minimum effective concentration was 10 sup -8 to 10 sup -7 M. for both PRL and GH. Pretreatment with indomethacin (10 sup -5 M.), but not tetrodotoxin (10 sup -5 M.), partially suppressed (p less than 0.05) the effects of PRL.ConclusionThese results suggest that PRL and GH directly and specifically produced contraction of the corpus cavernosum penis, resulting in erectile insufficiency, and that the effect of PRL is partially mediated by prostaglandin.