Huffman L, Hedge G A
Endocrinology. 1986 Feb;118(2):550-7. doi: 10.1210/endo-118-2-550.
The effects of vasoactive intestinal peptide (VIP) on thyroid blood flow and hormone levels were studied in rats. Tissue blood flow was determined from the distribution of radioactive microspheres after injection by cardiac puncture directly into the left ventricle of anesthetized rats. Initial results indicated that the systemic infusion of 6.25 micrograms VIP iv resulted in increased thyroid blood flow, but was also associated with hypotension, as measured by left ventricular pressure. In contrast, topical administration of VIP to the left of the thyroid increased blood flow to that lobe, but not to the right lobe, and produced no systemic cardiovascular effects. In a further set of experiments, graded doses of VIP were administered iv. Infusions of 6.25 and 0.625 micrograms VIP were associated with 2- to 3-fold increases in thyroid and pancreatic blood flows, but lower doses were ineffective. Blood flows to the adrenals, brain, small intestine, kidneys, and spleen were not altered by any dose of VIP. Mean left ventricular pressure was again reduced by the 6.25-micrograms dose of VIP, but was not affected by lower doses. The infusions of VIP had no effect on plasma TSH, T3, or T4 levels either 20 min or 2 h after treatment. These results suggest that thyroid blood flow is, in part, controlled by VIP and indicate that changes in thyroid blood flow can occur at doses of VIP that have no apparent effect on circulating thyroid hormone levels.
研究了血管活性肠肽（VIP）对大鼠甲状腺血流和激素水平的影响。通过将放射性微球经心脏穿刺直接注入麻醉大鼠的左心室后，根据其分布情况测定组织血流。初步结果表明，静脉注射6.25微克VIP进行全身输注会导致甲状腺血流增加，但同时也伴有低血压，这通过左心室压力来测量。相比之下，将VIP局部应用于甲状腺左侧会增加该叶的血流，但对右侧叶无影响，且不会产生全身心血管效应。在另一组实验中，静脉注射不同剂量的VIP。输注6.25微克和0.625微克VIP会使甲状腺和胰腺血流增加2至3倍，但较低剂量则无效。任何剂量的VIP均未改变肾上腺、脑、小肠、肾脏和脾脏的血流。6.25微克剂量的VIP再次使平均左心室压力降低，但较低剂量则无影响。治疗后20分钟或2小时，VIP输注对血浆促甲状腺激素（TSH）、三碘甲状腺原氨酸（T3）或甲状腺素（T4）水平均无影响。这些结果表明，甲状腺血流部分受VIP控制，并表明在对循环甲状腺激素水平无明显影响的VIP剂量下，甲状腺血流会发生变化。
