GENDER DIFFERENCES IN PRIMATE BRAIN STRUCTURES DETERMINED BY MRI IMAGES

目的：确定大脑中的性别差异 结构的恒河猴，我们测量了整个大脑的体积， 胼胝体、杏仁核大小MRI图像分析 方法. 结果本研究表明，全脑体积和 年轻成年雌性恒河猴胼胝体的大小 比年轻的成年男性小15%左右。 虽然雌性恒河猴的大脑重量比 男性，区域性的两性异形是不为人所知的， 非人类灵长类动物的大脑（Cupp和Uemura，1981）。 使用一种方法 MRI图像分析，测量全脑体积和大小 胼胝体（正中矢状面）和杏仁核（冠状面） 在41个从8个月到12个月的幼年到成年恒河猴的MRI图像中， 7.2岁的 对于脑体积，14个MRI图像（T-1加权， 1.3男5例，女3例，共60个连续冠状位图像 使用1.5至5.1岁的猴。 语料库的大小 在27个MRI图像中测量胼胝体和杏仁核（T-1周，3毫米 厚、矢状和冠状图像）， 8个月至7.2岁。 结果显示，大脑 雄性猴的体积随年龄略有增加; 1.5时为80.5（cm 3） 94.9岁，5.1岁。 雌猴的脑容量为 从1.5岁到4岁没有变化;范围是70.9到74.8。 到4岁时，男性大脑的平均体积为88.2q 1.9（SE）和女性大脑的72.2 q 0.7 cm 3。 平均 胼胝体面积从8个月到3岁增加0.56 (cm2)男性为0.93，女性为0.45 ~ 0.66。 平均面积 在8个月大后， 无变化; 1.08 q 0.03 cm 2。 我们已经做了大脑的核磁共振成像， 4只假两性雌猴及其图像分析 猴子将与上述年龄匹配的大脑结构进行比较。 正常的母猴 基于上述数据，我们 正计划比较大脑的结构差异 正常成年雌性和假雌雄同体的雌性猴子之间的关系， 在胎儿早期接受了睾酮治疗。 关键词MRI，脑 结构，性别差异，恒河猴

OBJECTIVE: To determine gender differences in the brain structures of rhesus monkeys, we measured the volume of whole brain, the size of corpus callosum, and amygdala by MRI image analysis methods. RESULTS This study suggests that the whole brain volume and the size of the corpus callosum of young adult female rhesus monkeys are approximately 15% smaller than those of young adult males. Although the brain weight of the female rhesus monkey is lighter than that of the male, regional sexual dimorphism is not well known in the brains of nonhuman primates (Cupp and Uemura, 1981). Using a method of MRI image analysis, we measured the whole brain volume and the size of the corpus callosum (mid-sagittal) and amygdala (coronal section) in 41 MRI images of juvenile to adult rhesus monkeys from 8 months to 7.2 years of age. For the brain volume, 14 MRI images (T-1 weighted, 1.3 mm thick, 60 serial coronal images) of 5 male and 3 female monkeys,1.5 to 5.1 years of age, were used. The sizes of the corpus callosum and amygdala were measured in 27 MRI images (T-1 w., 3 mm thick, sagittal and coronal images) of 12 male and 15 female monkeys, 8 months to 7.2 years of age. The results revealed that the brain volume of male monkeys slightly increased with age; 80.5 (cm3) at 1.5 years and 94.9 at 5.1 years. The brain volume of female monkeys was unchanged from the age of 1.5 to 4 years; the range was 70.9 to 74.8. By the age of 4 years, the average volume of the male brain was 88.2 q 1.9 (SE) and that of the female brain 72.2 q 0.7 cm3. The average area of the corpus callosum increases from 8 months to 3 years; 0.56 (cm2) to 0.93 in males and 0.45 to 0.66 in females. The average area of the amygdala after the age of 8 months in both genders was unchanged; 1.08 q 0.03 cm2. We have done MRI imaging of the brain of 4 pseudohermaphrodite female monkeys and the image anaysis of these monkeys will be compared to the above brain structures of age-matched normal female monkeys. FUTURE DIRECTIONS Based on the above data, we are planning to compare the structural differences of the brain between normal adult female and pseudohermaphrodite female monkeys who received testosterone during early fetal period. KEY WORDS MRI, brain structure, gender difference, rhesus monkey