Ito Tetsuya, Thidarmyint Hnin, Murata Takahiro, Inoue Hiroaki, Neyra Roel Mata, Kuwayama Hideto
Department of Animal Science, Obihiro University of Agriculture and Veterinary Medicine, 2-11 Nishi, Inada, Obihiro 080-8555, Japan.
J Endocrinol. 2006 Oct;191(1):113-9. doi: 10.1677/joe.1.06855.
These studies were designed to investigate the effects of i.v. administration of peptide YY(3-36) (PYY(3-36)) on feed intake, acylghrelin, and GH levels in castrated male pigs. Feed intake levels were evaluated during both ad libitum and fast-refed conditions, and plasma hormone responses were evaluated during fasting. During ad libitum feeding, i.v. injection of PYY(3-36) (30 microg/kg body weight, BW) significantly reduced feed intake levels within 3 h post-treatment. In the fast-refed condition, both single bolus injection (30 microg/kg BW) and i.v. infusion (0.25 microg/kg BW per min) of PYY(3-36) suppressed feed intake levels 1 h post-treatment. Duration of the elevation of plasma PYY levels induced by i.v. injection of porcine PYY(3-36) in ad libitum-fed pigs was longer compared with the values of fasted or fast-refed pigs. In the infusion study, the elevation of plasma PYY levels was maintained throughout the infusion period and values were reduced less than half at 15 min after termination of infusion. These results showed that the anorexigenic short-term effect of PYY(3-36) treatment corresponds to its half-life. However, i.v. PYY(3-36) injection did not influence plasma acyl-ghrelin levels. On the other hand, single bolus injection of PYY(3-36) increased plasma GH levels 30 min after treatment. Similar to previous findings in other mammalian species, the results of these studies show that PYY(3-36) can reduce feed intake levels; in particular, the effect is potent and acute in pigs. Furthermore, basal plasma PYY levels were higher in ad libitum-fed pigs than in fasted pigs suggesting that circulating PYY(3-36) levels influence satiety and contribute to the termination of feed intake in pigs.
这些研究旨在调查静脉注射肽YY（3-36）（PYY（3-36））对去势雄性猪采食量、酰基胃泌素和生长激素水平的影响。在自由采食和禁食再喂食条件下评估采食量水平，并在禁食期间评估血浆激素反应。在自由采食期间，静脉注射PYY（3-36）（30微克/千克体重，BW）在治疗后3小时内显著降低采食量水平。在禁食再喂食条件下，单次推注注射（30微克/千克BW）和静脉输注（0.25微克/千克BW每分钟）的PYY（3-36）在治疗后1小时抑制采食量水平。与禁食或禁食再喂食猪的值相比，在自由采食猪中静脉注射猪PYY（3-36）诱导的血浆PYY水平升高的持续时间更长。在输注研究中，血浆PYY水平在整个输注期间保持升高，并且在输注终止后15分钟时值降低不到一半。这些结果表明，PYY（3-36）治疗的短期厌食作用与其半衰期相对应。然而，静脉注射PYY（3-36）并不影响血浆酰基胃泌素水平。另一方面，单次推注注射PYY（3-36）在治疗后30分钟增加血浆生长激素水平。与先前在其他哺乳动物物种中的发现相似，这些研究结果表明PYY（3-36）可以降低采食量水平；特别是，这种作用在猪中是强效且急性的。此外，自由采食猪的基础血浆PYY水平高于禁食猪，这表明循环中的PYY（3-36）水平影响饱腹感并有助于猪采食量的终止。
