Haemisch A, Gärtner K
Department of Laboratory Animal Science, Hannover Medical School, Germany.
Physiol Behav. 1996 Jun;59(6):1117-22. doi: 10.1016/0031-9384(95)02174-4.
Adrenal activities of tyrosinehydroxylase (TH) and phenylethanolamine N-methyltransferase (PNMT) were compared between individually housed defeated intruders and socially housed residents (SR) (Experiment 1), and between individually housed defeated intruders and individually housed victor residents (Experiment 2). In addition, corticosterone titers were determined and dominance status of SR (dominant, subdominant active, and subdominant passive) considered. Defeats were induced twice a week for 6 consecutive weeks in short resident-intruder encounters. The main findings were: 1) within the groups of SR, TH and PNMT activities were high in dominant and low in subdominant-passive mice; 2) in Experiment 1, TH activities of individually housed defeated intruders were low like those of subdominant-passive SR whereas their PNMT activities were high like those of dominant SR; 3) in Experiment 2, TH activities were low in both categories of individually kept mice whereas PNMT activities were significantly elevated in the defeated intruders; 4) in both experiments, PNMT activities of intruders correlated significantly with the accumulated number of attacks they had received throughout all resident-intruder tests. Findings show separate effects of permanent social stimulation and of episodic experience of defeats on adrenal catecholamine synthesis. Lack of permanent social stimulation decreased adrenal TH and PNMT activities whereas repeated episodic experience of defeats specifically increased PNMT but not TH activities in individually housed mice.
在单独饲养的战败入侵者与群居的定居者（SR）之间（实验1），以及在单独饲养的战败入侵者与单独饲养的胜利定居者之间（实验2），比较了酪氨酸羟化酶（TH）和苯乙醇胺N-甲基转移酶（PNMT）的肾上腺活性。此外，还测定了皮质酮滴度，并考虑了SR的优势地位（优势、次优势活跃和次优势被动）。在短暂的定居者-入侵者相遇中，每周诱导战败两次，持续6周。主要发现如下：1）在SR组中，优势小鼠的TH和PNMT活性高，次优势被动小鼠的活性低；2）在实验1中，单独饲养的战败入侵者的TH活性与次优势被动SR的相似较低，而其PNMT活性与优势SR的相似较高；3）在实验2中，两类单独饲养的小鼠的TH活性均较低，而战败入侵者的PNMT活性显著升高；4）在两个实验中，入侵者的PNMT活性与它们在所有定居者-入侵者测试中所受到的累积攻击次数显著相关。研究结果表明，永久性社会刺激和战败的偶发性经历对肾上腺儿茶酚胺合成有不同影响。缺乏永久性社会刺激会降低肾上腺TH和PNMT活性，而反复的战败偶发性经历会使单独饲养的小鼠的PNMT活性特异性增加，但不会使TH活性增加。
