Strüder H K, Hollmann W, Weicker H, Schiffer T, Weber K
Institute of Sports Games, German Sport University, Cologne.
Acta Physiol Scand. 1999 Mar;165(3):265-9. doi: 10.1046/j.1365-201x.1999.00500.x.
Responses of plasma prolactin (PRL) concentration to acute and repeated changes in blood oxygen partial pressure (PO2a) at rest were investigated in two studies (A; B), with special reference to possible effects mediated via serotonin (5-HT) synthesis. In A, nine male subjects inhaled for 105 min gas containing different oxygen fractions for 6 days. Gas concentrations consisted of 14% (A14), 21 % (A21), 40% (A40), 60% (A60) and 80% (A80) O2 mixed with N2 as well as 100% O2 (A100). Venous and capillary blood samples were drawn before and every 15 min during gas inhalation for analysis of plasma PRL and PO2a. In B, two groups of subjects (B I; B II) were exposed to 30 min day(-1) of gas inhalation over 14 consecutive days. Gas concentration consisted for B I of 14% O2/86% N2 and for B II of 100% O2. During pre- and post-examination a baseline blood sample was drawn, followed by a neuroendocrine test of serotonergic function using a partial 5-HT1A receptor agonist (60 mg of buspirone hydrochloride). In A, each increase of inhaled oxygen fraction also resulted in higher blood POb2a. In A14, A21 and A40, plasma PRL concentrations did not change from basal level. Increases in plasma PRL concentration were found in A60 after 30 min as well as in A80 and A100 after 15 min. A higher blood PO2a induced a higher plasma PRL secretion but also an earlier decline from peak plasma PRL value despite continued inhalation of the respective oxygen concentration. During post-examination in B, basal plasma PRL concentrations were increased in B I and decreased in B II. Plasma PRL response to stimulation challenge was not affected by treatments. Thus, chronic adaptations of basal plasma PRL concentrations to decreased/increased blood PO2a were not related to up/down-regulation, respectively, of central serotonergic receptor function.
在两项研究（A；B）中，研究了静息状态下血浆催乳素（PRL）浓度对血氧分压（PO2a）急性和反复变化的反应，特别关注了通过血清素（5-HT）合成介导的可能影响。在研究A中，9名男性受试者连续6天吸入含不同氧分数的气体105分钟。气体浓度包括14%（A14）、21%（A21）、40%（A40）、60%（A60）和80%（A80）的O2与N2混合，以及100%O2（A100）。在气体吸入前及吸入过程中每15分钟采集静脉和毛细血管血样，用于分析血浆PRL和PO2a。在研究B中，两组受试者（B I；B II）连续14天每天暴露于30分钟的气体吸入。B I组的气体浓度为14%O2/86%N2，B II组为100%O2。在检查前和检查后采集基线血样，然后使用部分5-HT1A受体激动剂（60毫克盐酸丁螺环酮）进行血清素能功能的神经内分泌测试。在研究A中，吸入氧分数的每次增加也导致血液PO2a升高。在A14、A21和A40中，血浆PRL浓度与基础水平相比没有变化。在A60中，30分钟后血浆PRL浓度升高，在A80和A100中，15分钟后升高。较高的血液PO2a诱导较高的血浆PRL分泌，但尽管继续吸入各自的氧浓度，血浆PRL峰值后也较早下降。在研究B的检查后，B I组的基础血浆PRL浓度升高，B II组降低。血浆PRL对刺激挑战的反应不受治疗影响。因此，基础血浆PRL浓度对降低/升高的血液PO2a的慢性适应分别与中枢血清素能受体功能的上调/下调无关。
