Mesenteric infusion of a volatile fatty acid prevents body weight loss and transiently restores luteinising hormone pulse frequency in ovariectomised, food-restricted ewes.
Mesenteric infusion of a volatile fatty acid prevents body weight loss and transiently restores luteinising hormone pulse frequency in ovariectomised, food-restricted ewes.
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肠系膜输注挥发性脂肪酸可防止卵巢切除、食物限制的母羊体重减轻并暂时恢复黄体生成素脉冲频率。
DOI：
10.1111/j.1365-2826.2011.02173.x
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发表时间：
2011
影响因子：
3.2
通讯作者：
Clarke,IJ
中科院分区：
文献类型：
--
作者：
Szymanski,LA;Schneider,JE;Satragno,A;Dunshea,FR;Clarke,IJ
脉冲式促黄体生成激素（LH）分泌被食物限制抑制，并迅速恢复返回蟾蜍自由。喂养伴随着游离脂肪酸氧化的增加，虽然没有增加血浆瘦素浓度或体脂肪含量在卵巢切除母羊。食物的摄入可通过增加可氧化代谢底物的可用性来刺激LH分泌。瘤胃消化的特征在于挥发性脂肪酸的产生，其中丙酸盐是主要的致炎底物，葡萄糖和丙酸盐在多种组织中都是可氧化的。为了检查肠系膜丙酸盐浓度的增加是否足以恢复限食期间的脉冲式LH分泌，成年、限食、低促性腺激素、卵巢切除的母羊接受肠系膜静脉输注5 μmol/min/kg体重（BW）丙酸盐或生理盐水，而正常体重、自由采食的母羊接受肠系膜输注生理盐水，持续10天。 在10天输注期开始前每10分钟采集一次血样，持续5小时，并在第1天下午输注的前5小时以及第2、7和10天上午继续采集血样。 在输注后第1天和第2天，丙酸盐输注、限食和自由进食、盐水输注母羊的LH脉冲频率显著高于限食盐水输注母羊，但在第7天和第10天并非如此，仅盐水输注、限食组体重显著减轻。这些结果表明，生殖系统可以迅速响应注入的代谢燃料，如丙酸，虽然持续恢复的脉动LH分泌需要更多的增加，在这个单一的代谢底物。
Pulsatile luteinising hormone (LH) secretion is suppressed by food restriction and rapidly restored by return toad lib.feeding concomitant with an increase in the oxidation of free fatty acids, although there is no increase in plasma leptin concentrations or body fat content in ovariectomised ewes. The ingestion of food may stimulate LH secretion by increasing availability of oxidisable metabolic substrates. Ruminal digestion is characterised by the production of volatile fatty acids and, of these, propionate is the major gluconeogenic substrate, and both glucose and propionate are oxidisable in a variety of tissues. To examine whether increases in mesenteric propionate concentrations are sufficient for restoration of pulsatile LH secretion during a period of food restriction, adult, food‐restricted, hypogonadotrophic, ovariectomised ewes received mesenteric vein infusions of 5 μmol/min/kg body weight (BW) propionate or saline, whereas normal weight,ad lib.‐fed ewes received mesenteric infusions of saline for 10 days. Blood samples were taken every 10 min for 5 h before the start of the 10‐day infusion period, and continued throughout the first 5 h of infusion on the afternoon of day 1, and in the morning on days 2, 7 and 10. Propionate‐infused, food‐restricted andad lib.‐fed, saline‐infused ewes showed a significantly higher LH pulse frequency compared to that of food‐restricted‐saline‐infused ewes on postinfusion days 1 and 2 but not on days 7 and 10, and only the saline‐infused, food‐restricted group lost a significant amount of body weight. These results indicate that the reproductive system can respond acutely to infusion of metabolic fuels such as propionate, although a sustained recovery of pulsatile LH secretion requires more than an increase in this single metabolic substrate.