摘要
A deficit in spatial memory has been taken as an early predictor of Alzheimer’s disease(AD) or mild cognitive impairment(MCI). The uncinate fasciculus(UF) is a long-range white-matter tract that connects the anterior temporal lobe with the orbitofrontal cortex(OFC)in primates. Previous studies have shown that the UF impairment associated with spatial memory deficits may be an important pathological change in aging and AD, but its exact role in spatial memory is not well understood. The pathway arising from the postrhinal cortex(POR) and projecting to the ventrolateral orbitofrontal cortex(vlOFC)performs most of the functions of the UF in rodents.Although the literature suggests an association between spatial memory and the regions connected by the POR–vlOFC pathway, the function of the pathway in spatialmemory is relatively unknown. To further illuminate the function of the UF in spatial memory, we dissected the POR–vlOFC pathway in mice. We determined that the POR–vlOFC pathway is a glutamatergic structure, and that glutamatergic neurons in the POR regulate spatial memory retrieval. We also demonstrated that the POR–vlOFC pathway specifically transmits spatial information to participate in memory retrieval. These findings provide a deeper understanding of UF function and dysfunction related to disorders of memory, as in MCI and AD.
A deficit in spatial memory has been taken as an early predictor of Alzheimer’s disease(AD) or mild cognitive impairment(MCI). The uncinate fasciculus(UF) is a long-range white-matter tract that connects the anterior temporal lobe with the orbitofrontal cortex(OFC)in primates. Previous studies have shown that the UF impairment associated with spatial memory deficits may be an important pathological change in aging and AD, but its exact role in spatial memory is not well understood. The pathway arising from the postrhinal cortex(POR) and projecting to the ventrolateral orbitofrontal cortex(vlOFC)performs most of the functions of the UF in rodents.Although the literature suggests an association between spatial memory and the regions connected by the POR–vlOFC pathway, the function of the pathway in spatialmemory is relatively unknown. To further illuminate the function of the UF in spatial memory, we dissected the POR–vlOFC pathway in mice. We determined that the POR–vlOFC pathway is a glutamatergic structure, and that glutamatergic neurons in the POR regulate spatial memory retrieval. We also demonstrated that the POR–vlOFC pathway specifically transmits spatial information to participate in memory retrieval. These findings provide a deeper understanding of UF function and dysfunction related to disorders of memory, as in MCI and AD.
基金
supported by the National Major Science and Technology Program of China(2016YFC1306700)
the National Natural Science Foundation of China(81420108012,81671046,81425010 and 31630031)
the Jiangsu Provincial Medical Program for Distinguished Scholars(2016006)
Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX18_0167),China
