Substantial decline of phasic dopamine signaling in senescent male rats does not impact dopamine-dependent Pavlovian conditioning.
Substantial decline of phasic dopamine signaling in senescent male rats does not impact dopamine-dependent Pavlovian conditioning.
复制标题
衰老雄性大鼠阶段性多巴胺信号的大幅下降并不影响多巴胺依赖性巴甫洛夫条件反射。
DOI：
10.1101/2023.12.21.572806
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Phillips,PaulEM
中科院分区：
文献类型：
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作者：
Sandberg,StefanG;Sanford,ChristinaA;Phillips,PaulEM
正常衰老与影响财务决策的认知能力下降有关。决策的基本特征之一是概率估计，其中涉及到脑桥核多巴胺信号。在这里，我们使用快速扫描循环伏安法来探测多巴胺信号的年龄差异，并通过药理学操作来测试巴甫洛夫条件反射的多巴胺依赖性的年龄差异。我们发现，在相位多巴胺信号奖励交付的差异，无条件和条件刺激，但没有成人和衰老组之间的条件方法的差异。此外，我们发现氟噻吨（225 μg/kg，i. p.）成年组部分抑制条件性通路，而老年组完全阻断条件性通路。浓度进一步增加至300 μg/kg，腹腔注射，导致两个年龄组的条件接近行为完全抑制。因此，虽然衰老动物的丘脑核中的阶段性多巴胺信号在浓度上大大减少，但这些动物保持多巴胺依赖性巴甫洛夫条件反射。
Normal aging is associated with cognitive decline which impacts financial decision making. One of the underlying features of decision making is probability estimation, in which nucleus accumbens dopamine signaling has been implicated. Here we used fast-scan cyclic voltammetry to probe for age differences in dopamine signaling, and pharmacological manipulation to test for age differences in the dopamine dependence of Pavlovian conditioning. We found differences in phasic dopamine signaling to reward delivery, and unconditioned and conditioned stimuli, but no difference in conditioned approach between adult and senescent groups. In addition, we found that dopamine receptor antagonism with flupenthixol (225 μg/kg, i.p.) partially inhibited conditioned approach in the adult group, whereas it completely blocked conditioned approach in the senescent group. Further increase in concentration to 300 μg/kg, i.p. resulted in complete inhibition of conditioned approach behavior in both age groups. Therefore, while phasic dopamine signaling in the nucleus accumbens of senescent animals is greatly diminished in concentration, these animals maintain dopamine dependent Pavlovian conditioning.