de Jong A
J Endocrinol. 1982 Mar;92(3):357-70. doi: 10.1677/joe.0.0920357.
To determine whether volatile fatty acids (VFA) are involved in the regulation of plasma concentrations of insulin of glucagon in the goat, VFA, separately or in combination, were administered into the jugular vein, the portal vein or the rumen, and their effect on pancreatic hormones as well as on VFA measured in venous blood. Propionate, n-butyrate and n-valerate, but not acetate, injected in pharmacological doses, were potent stimuli not only of the secretion into the plasma of insulin but also of glucagon. As regards insulin, the response to VFA was probably not mediated to an appreciable extent by glucose or glucagon. Beta-Hydroxybutyrate did not mediate the effect of n-butyrate on insulin and glucagon. The effects of VFA appear to be peculiar to the ruminant since in the rat injection of similar doses resulted in either no changes or very small changes of plasma insulin and glucagon. Intraportal infusions over 4h of mixtures of VFA, resulting in less extreme, more physiological blood concentration of VFA, elicited sudden transient increases in insulin and to a lesser extent in glucagon. After these peaks insulin and glucagon declined to preinfusion levels and remained virtually unaltered during the remainder of the infusion in spite of sustained, raised concentrations of VFA in the peripheral circulation. These results suggest that under these conditions the rate of increase of VFA is a signal for the secretion of pancreatic hormones. Intraruminal infusions, representing a more physiological route of administration, of single VFA at high rates resulted in a small increase in insulin for propionate infusion only, whereas a mixture of VFA at a physiological rate induced barely any change in insulin or glucagon. It is concluded that under physiological conditions the rate of increase of VFA may contribute to the insulin secretion in the free-feeding goat, but it is unlikely that VFA are the sole controlling agents of insulin release. It is even less probable that the release of glucagon is governed by VFA in the free-feeding goat.
为了确定挥发性脂肪酸（VFA）是否参与山羊胰高血糖素胰岛素血浆浓度的调节，将VFA单独或联合注入颈静脉、门静脉或瘤胃，并观察其对胰腺激素以及静脉血中VFA的影响。药理剂量注射的丙酸、正丁酸和正戊酸，而非乙酸，不仅是胰岛素分泌到血浆中的有效刺激物，也是胰高血糖素的有效刺激物。就胰岛素而言，对VFA的反应可能在很大程度上不是由葡萄糖或胰高血糖素介导的。β-羟基丁酸不介导正丁酸对胰岛素和胰高血糖素的作用。VFA的作用似乎是反刍动物所特有的，因为在大鼠中注射相似剂量的VFA导致血浆胰岛素和胰高血糖素要么没有变化，要么变化非常小。4小时内门静脉输注VFA混合物，导致VFA血液浓度不那么极端、更接近生理水平，引发胰岛素突然短暂升高，胰高血糖素升高程度较小。在这些峰值之后，胰岛素和胰高血糖素降至输注前水平，并且在输注的其余时间内几乎保持不变，尽管外周循环中VFA浓度持续升高。这些结果表明，在这些条件下，VFA的增加速率是胰腺激素分泌的信号。瘤胃内输注单一VFA，以更高的速率代表更生理的给药途径，仅丙酸盐输注导致胰岛素略有增加，而以生理速率输注VFA混合物几乎不会引起胰岛素或胰高血糖素的任何变化。得出的结论是，在生理条件下，VFA的增加速率可能有助于自由采食山羊的胰岛素分泌，但VFA不太可能是胰岛素释放的唯一控制因素。在自由采食山羊中，胰高血糖素的释放由VFA控制的可能性更小。
