Kelberman Michael A, Winther Kelly E, Medvedeva Yana M, Donaldson Zoe R
bioRxiv. 2024 May 17:2024.05.17.594752. doi: 10.1101/2024.05.17.594752.
Pair bonds powerfully modulate health, which becomes particularly important when facing the detrimental effects of aging. To examine the impact of aging on relationship formation and response to loss, we examined behavior in 6-, 12-, and 18-month male and female prairie voles, a monogamous species that forms mating-based pair bonds. We found that older males (18-months) bonded quicker than younger voles, while similarly aged female voles increased partner directed affiliative behaviors. Supporting sex differences in bonding behaviors, we found that males were more likely to sample both partner and novel voles while females were more likely to display partner preference during the initial 20 minutes of the test. Using partner separation to study loss, we observed an erosion of partner preference only in 12-month females, but an overall decrease in partner-directed affiliation in females across all groups, but not in males. Finally, we found that the number of oxytocin, but not vasopressin, cells in the paraventricular hypothalamus increased during aging. These results establish prairie voles as a novel model to study the effects of normal and abnormal aging on pair bonding.
18-month male voles demonstrate accelerated bond formation18-month female voles increase partner-directed huddling after 2 wksBonds erode faster in 12-month female voles after partner separationFemale behavior from partner preference tests is reflected in free interactionThe number of paraventricular hypothalamus oxytocin cells increase during aging.
伴侣关系有力地调节健康状况，在面对衰老的有害影响时这一点尤为重要。为了研究衰老对关系形成及对失去的反应的影响，我们检测了6个月、12个月和18个月大的雄性和雌性草原田鼠的行为，草原田鼠是一种形成基于交配的伴侣关系的一夫一妻制物种。我们发现，老年雄性（18个月大）比年轻田鼠更快地建立伴侣关系，而同龄雌性田鼠增加了指向伴侣的亲和行为。支持伴侣关系行为中的性别差异，我们发现雄性在测试的最初20分钟内更有可能对伴侣和田鼠新对象都进行接触，而雌性更有可能表现出伴侣偏好。利用伴侣分离来研究失去，我们观察到只有12个月大的雌性出现伴侣偏好的减弱，但所有组的雌性中指向伴侣的亲和行为总体上都减少了，而雄性则没有。最后，我们发现衰老过程中室旁下丘脑的催产素细胞数量增加，而加压素细胞数量未增加。这些结果确立了草原田鼠作为研究正常和异常衰老对伴侣关系影响的新模型。
18个月大的雄性田鼠表现出加速的伴侣关系形成；18个月大的雌性田鼠在2周后增加指向伴侣的蜷缩行为；伴侣分离后，12个月大的雌性田鼠的伴侣关系更快地消退；伴侣偏好测试中的雌性行为反映在自由互动中；衰老过程中室旁下丘脑的催产素细胞数量增加。
