Department of Psychology, University of California, Davis, One Shields Ave., Davis, CA 95616, United States of America.
Department of Psychology, University of California, Davis, One Shields Ave., Davis, CA 95616, United States of America.
Horm Behav. 2022 May;141:105129. doi: 10.1016/j.yhbeh.2022.105129. Epub 2022 Feb 12.
Maternal experience can promote a long-lasting increase in maternal motivation. This maintenance of caregiving behaviors, rather than avoidant or agnostic responses towards young, is advantageous for the survival of subsequent offspring. We have previously reported that maternal motivation is associated with differential immediate early gene expression in central motivation circuits and aversion circuits. Here we ask how these circuits come to differentially respond to infant cues. We used Targeted Recombination in Active Populations (TRAP) to identify cells that respond to pups in maternally hesitant TRAP2;Ai14 virgin female mice. Following an initial 60 min exposure to foster pups, virgin TRAP2;Ai14 mice were injected with 4-hydroxytamoxifen to induce recombination in c-Fos expressing cells and subsequent permanent expression of a red fluorescent reporter. We then examined whether the same cells that encode pup cues are reactivated during maternal memory retrieval two weeks later using c-Fos immunohistochemistry. Whereas initial pup exposure induced c-Fos activation exclusively in the medial preoptic area (MPOA), following repeated experience, c-Fos expression was significantly higher than baseline in multiple regions of maternal and central aversion circuits (e.g., ventral bed nucleus of the stria terminalis, nucleus accumbens, basolateral amygdala, prefrontal cortex, medial amygdala, and ventromedial nucleus of the hypothalamus). Further, cells in many of these sites were significantly reactivated during maternal memory retrieval. These data suggest that cells across both maternal motivation and central aversion circuits are stably responsive to pups and thus may form the cellular representation of maternal memory.
母体经验可以促进母体动机的持久增加。这种维持照顾行为,而不是对幼崽采取回避或不可知的反应,有利于随后后代的生存。我们之前报告过,母体动机与中央动机回路和回避回路中的差异即时早期基因表达有关。在这里,我们想知道这些回路是如何对婴儿线索做出不同反应的。我们使用靶向重组在活跃群体(TRAP)来识别对幼崽有反应的细胞在犹豫的 TRAP2 ; Ai14 处女母鼠中。在最初接触寄养幼崽 60 分钟后,TRAP2 ; Ai14 处女小鼠被注射 4-羟基他莫昔芬,以诱导 c-Fos 表达细胞的重组和随后红色荧光报告基因的永久表达。然后,我们使用 c-Fos 免疫组织化学检查相同的细胞是否在两周后的母体记忆检索过程中重新激活,这些细胞编码幼崽线索。虽然最初的幼崽暴露仅在中脑前腹侧区(MPOA)中诱导 c-Fos 激活,但在反复体验后,c-Fos 表达在多个母体和中央回避回路区域(例如,腹侧终纹床核、伏隔核、基底外侧杏仁核、前额叶皮层、内侧杏仁核和下丘脑腹内侧核)显著高于基线。此外,许多这些部位的细胞在母体记忆检索过程中明显重新激活。这些数据表明,母体动机和中央回避回路中的细胞都对幼崽有稳定的反应,因此可能形成母体记忆的细胞代表。