The aim of the current study was to determine effects of intracerebroventricular (ICV) and intraperitoneal (i.p.) administration of Methylamine (MET) and possible interactions with nitric oxide (NO) and TAAR₁ pathways in 24-h fasted (FD₂₄) and ad libitum layer-type chicken. In experiment 1, FD₂₄ chicken ICV injected with MET (15, 30, 45, 60 and 75 μg). In experiment 2, ICV injection of MET (15, 30, 45, 60 and 75 μg) was injected in the ad libitum birds. Experiments 3–4 were similar to experiments 1–2, except chicken i.p. injected with MET (15, 30, 45, 60 and 75 mg/kg). In experiment 5, FD₂₄ birds ICV injected with l-NAME (NO synthesis inhibitor, 100 nmol), MET (75 μg) and co-injection of l-NAME + MET. Experiment 6 was similar to experiment 5, except, ad libitum birds received injections. In experiment 7, FD₂₄ chicken i.p. injected with l-NAME (100 mg/kg), MET (75 mg/kg) and co-injection of l-NAME + MET. In experiment 8, FD₂₄ birds ICV injected with RO5256390 (selective TAAR₁ agonist, 10, 20 and 40 μg). In experiment 9, ad libitum birds ICV injected with RO5256390 (10, 20 and 40 μg). In experiment 10, FD₂₄ birds ICV injected with RO5256390 (10 μg), MET (75 μg) and their co-injection. Experiment 11 was similar to experiment 10, except, ad libitum birds received ICV injections. In experiment 12, FD₂₄ chicken i.p. injected with RO5256390 (2.5, 5 and 10 mg/kg). In experiment 13, FD₂₄ chicken i.p. injected with RO5256390 (2.5 mg/kg), MET (75 mg/kg) and RO5256390 + MET. Then cumulative food intake was determined until 120 min after injection. According to the results, ICV injection of MET decreased food intake in FD₂₄ and ad libitum chicken (P < 0.05). MET (i.p.) diminished food consumption in fasted (P < 0.05) but not in ad libitum chicken (P> 0.05). Co-injection of the l-NAME + MET significantly decreased MET-induced hypophagia in FD₂₄ and ad libitum chicken (P < 0.05). MET-induced hypophagia (i.p.) weakened by l-NAME in FD₂₄ chicken (P < 0.05). RO5256390 decreased food intake in FD₂₄ and ad libitum chicken (P < 0.05). Co-injection of RO5256390 + MET increased MET-induced hypophagia in FD₂₄ and ad libitum chicken (P < 0.05). RO5256390 decreased food intake in FD₂₄ chicken (P < 0.05). Co-injection of the RO5256390 + MET amplified MET-induced hypophagia in FD₂₄ chicken (P < 0.05). Based on the findings, MET-induced hypophagia is mediated via NO and TAAR₁ pathways on food intake in layer chicken.

本研究的目的是确定禁食24小时（FD ₂₄）和ad中脑室内（ICV）和腹膜内（ip）给予甲胺（MET）的作用以及与一氧化氮（NO）和TAAR ₁途径的可能相互作用任意层蛋鸡。在实验1中，FD ₂₄鸡ICV注射了MET（15、30、45、60和75μg）。在实验2中，将ICV注射的MET（15、30、45、60和75μg）注射到随意的禽类中。实验3–4与实验1-2类似，只是鸡腹腔注射MET（15、30、45、60和75 mg / kg）。在实验5中，FD ₂₄鸟ICV注射了l-NAME（NO合成抑制剂，100 nmol），MET（75μg）并共同注射l -NAME + MET。实验6与实验5类似，除了自由的鸟类接受注射。在实验7中，FD ₂₄鸡腹膜内注射1- NAME（100 mg / kg），MET（75 mg / kg）并同时注射1 - NAME + MET。在实验8中，FD ₂₄禽类ICV注射了RO5256390（选择性TAAR ₁激动剂，10、20和40μg）。在实验9中，随意给禽类ICV注射RO5256390（10、20和40μg）。在实验10中，FD ₂₄禽ICV注射了RO5256390（10μg），MET（75μg）及其共同注射。实验11与实验10相似，除了随意的鸟接受ICV注射。在实验12中，FD ₂₄鸡腹腔注射RO5256390（2.5、5和10 mg / kg）。在实验13中，FD ₂₄鸡腹腔注射了RO5256390（2.5 mg / kg），MET（75 mg / kg）和RO5256390 + MET。然后确定累积的食物摄入量，直到注射后120分钟。根据结果​​，ICV注射MET会降低FD ₂₄和随意鸡的食物摄入（P <0.05）。MET（ip）可以减少禁食中的食物消耗（P <0.05），但不影响自由放养的鸡肉中的食物消耗（P> 0.05）。l的共注入-NAME + MET显着降低FD ₂₄和随意鸡中MET引起的吞咽不足（P <0.05）。在FD ₂₄鸡中，MET引起的吞咽（ip）被l -NAME减弱（P <0.05）。RO5256390减少了FD ₂₄和随意鸡的食物摄入（P <0.05）。共注射RO5256390 + MET可增加FD ₂₄和随意放养鸡的MET引起的吞咽不足（P <0.05）。RO5256390减少了FD ₂₄鸡的摄食量（P <0.05）。在FD ₂₄鸡中共注射RO5256390 + MET扩增了MET引起的吞咽不足（P <0.05）。基于这些发现，介导的MET引起的吞咽不足被介导通过蛋鸡的NO和TAAR ₁途径摄取食物。