Villablanca J R, Schmanke T D, Crutcher H A, Sung A C, Tavabi K
Departments of Psychiatry and Biobehavioral Sciences and of Neurobiology, Mental Retardation Research Center and Brain Research Institute, University of California, Los Angeles, CA 90024-1759, USA.
Brain Res Dev Brain Res. 2000 Jul 30;122(1):21-33. doi: 10.1016/s0165-3806(00)00047-x.
As a continuation of the morphometric studies on the preceding paper, here we report on the rate of growth of the caudate nucleus (n.), thalamus, red n., and the substantia (s.) nigra using, with few exceptions, the same cohort of cats. The same previously used brains (n=64 cats) were allocated to the following age groups: fetal (E) 59 days, postnatal (P) days 1, 7, 15, 30, 45, 60, 90, 120, and 180. Sixteen additional cats, interspersed within the groups, were substituted for the red n. and s. nigra studies. There were six subjects per group (except for E59, n=4). Using a projection microscope and cytochrome oxidase-stained coronal sections, a combined (left plus right sides) total of 4693, 3822, 1636, and 1180 sections were drawn for the caudate, thalamus, s. nigra, and red n., respectively. With computer assistance, the drawings were digitized to calculate mean cross-sectional areas and then the mean volume of each structure per group. The growth time tables for the caudate n., thalamus and s. nigra were fairly synchronous. In terms of percentage of the adult volume, for the left side (both sides grew at a similar rate), the three structures grew at a fast pace between E59 and P30. Thus, at E59 their respective percentages relative to adult volume were 23.7, 29.8 and 22.6% and by P30 the percentages were within adult range (85.2, 115.1 and 87.5%, respectively). Starting at P30, for the thalamus and at P45 for the caudate n., there was a consistent tendency to an overgrow which ranged between 4.3 and 30.9% (at P180, P<0.5) for the caudate and between 0.3 and 15.1% for the thalamus. In addition, starting at P30, the right thalamus tended to be consistently larger than the left by a margin ranging between 0.5 and 11.2% (P120, P<0.05). The red n. grew at a different, slower pace. Starting from a fetal volume equivalent to an 18.6% of adult size, its volume was only a 61.0% of the adult value at P30 and came within range of adulthood size only by P60 (81. 3%). Neither the s. nigra nor the red n. showed any consistent tendency to overgrow or to asymmetry. These findings are discussed in the context of the literature. Furthermore, we discuss general conclusions and considerations pertaining to both papers as well as draw comparisons with the maturational time tables of other developmental landmarks in cats. Finally, in a comparison with growth of human brain structures, we point at the limitations and complexities involved in studying human material and, noting interspecies similarities, we propose that the present data from an advanced gyrencephalic mammal may form the bases for a model of structures maturation in humans.
作为前文形态测量研究的延续，本文报告尾状核、丘脑、红核及黑质的生长速率，除少数例外，研究对象为同一组猫。将之前使用的相同大脑（n = 64只猫）分为以下年龄组：胎儿期（E）59天、出生后（P）1天、7天、15天、30天、45天、60天、90天、120天和180天。在各年龄组中穿插加入16只额外的猫，用于红核和黑质的研究。每组有6个研究对象（E59组除外，n = 4）。使用投影显微镜和细胞色素氧化酶染色冠状切片，分别为尾状核、丘脑、黑质和红核绘制了总共4693、3822、1636和1180张联合切片（左侧加右侧）。在计算机辅助下，将这些绘图数字化以计算平均横截面积，进而计算每组各结构的平均体积。尾状核、丘脑和黑质的生长时间表相当同步。就相对于成年体积的百分比而言，左侧（两侧生长速率相似）的这三个结构在E59至P30期间快速生长。因此，在E59时，它们相对于成年体积的各自百分比分别为23.7%、29.8%和22.6%，到P30时，这些百分比已在成年范围内（分别为85.2%、115.1%和87.5%）。从P30开始，丘脑以及从P45开始，尾状核出现持续过度生长的趋势，尾状核的过度生长幅度在4.3%至30.9%之间（在P180时，P < 0.5），丘脑的过度生长幅度在0.3%至15.1%之间。此外，从P30开始，右侧丘脑往往始终比左侧大，幅度在0.5%至11.2%之间（在P120时，P < 0.05）。红核的生长速度不同，较慢。从相当于成年大小18.6%的胎儿期体积开始，其体积在P30时仅为成年值的61.0%，直到P60才达到成年大小范围（81.3%）。黑质和红核均未表现出任何持续的过度生长或不对称趋势。将结合文献对这些发现进行讨论。此外，我们还讨论了与两篇论文相关的总体结论和思考，并与猫的其他发育标志的成熟时间表进行比较。最后，在与人类脑结构生长的比较中，我们指出研究人类材料所涉及的局限性和复杂性，并注意到种间相似性，我们提出来自高级脑回哺乳动物的当前数据可能构成人类结构成熟模型的基础。
