Shamgochian M D, Leeman S E
Department of Physiology, University of Massachusetts Medical School, Worcester 01655.
Endocrinology. 1992 Aug;131(2):871-5. doi: 10.1210/endo.131.2.1379165.
Substance P (SP) is present in the anterior pituitary gland (AP), and its concentration there is regulated by the hormonal status of the animal. The observation that SP is releasable from hemipituitaries in a K(+)-stimulated, Ca(2+)-dependent manner and the demonstration of SP-binding sites in the AP have led to the suggestion that SP participates in a paracrine or autocrine manner in the regulation of AP function. Contradictory reports of the effects of SP on the secretion of AP hormones, particularly LH, led us to address the question of whether SP can act directly on the AP to effect LH secretion. We found that SP (100 nM) can stimulate LH release (300-400% of control values) in short term cultures of AP cells and that this effect varies as a function of the age and sex of the animal. There was no significant effect of SP on the release of LH from AP cells of male and female prepubertal rats (20-30 days). During the peripubertal period (30-35 days), a sharp increase in the response to SP occurred in both sexes. This responsiveness was dose dependent and persisted at all ages studied in AP cells from the female rat. In contrast, the responsiveness of AP cells from male rats that developed during the peripubertal period diminished during maturation and was absent after 60 days of age. When adult female rats were exposed to androgens for 6 weeks in vivo and tested for the ability of SP to stimulate the LH secretion, the response was significantly diminished. These studies support the speculation that SP has a functional role in the secretion of LH.
P物质（SP）存在于垂体前叶（AP）中，其在垂体前叶中的浓度受动物激素状态的调节。有观察表明，SP能以K⁺刺激、Ca²⁺依赖的方式从半垂体中释放出来，并且在垂体前叶中发现了SP结合位点，这表明SP以旁分泌或自分泌的方式参与垂体前叶功能的调节。关于SP对垂体前叶激素分泌，尤其是促黄体生成素（LH）分泌影响的报道相互矛盾，这促使我们研究SP是否能直接作用于垂体前叶以影响LH分泌。我们发现，在垂体前叶细胞的短期培养中，SP（100 nM）能刺激LH释放（达到对照值的300 - 400%），并且这种作用因动物的年龄和性别而异。SP对青春期前雄性和雌性大鼠（20 - 30天）垂体前叶细胞释放LH没有显著影响。在青春期前后（30 - 35天），两性对SP的反应都急剧增加。这种反应性呈剂量依赖性，并且在对雌性大鼠垂体前叶细胞研究的所有年龄段都持续存在。相比之下，青春期前后发育的雄性大鼠垂体前叶细胞的反应性在成熟过程中逐渐减弱，60日龄后则消失。当成年雌性大鼠在体内接受6周雄激素处理并测试SP刺激LH分泌的能力时，反应显著减弱。这些研究支持了SP在LH分泌中具有功能性作用的推测。
