Development of cerebral sulci and gyri in ferrets (Mustela putorius)

The present study aimed to clarify sulcation and gyration patterns in the developing cerebrum of ferrets. While the brain weight and fronto-occipital length of the cerebral hemisphere reached a plateau by postnatal day (PD) 42, the cerebral width reached a plateau at the rostral region by PD 21, and subsequently at the caudal region by PD 42. The ferret cerebrum already showed a convoluted surface with indentations of coronal and rostral suprasylvian sulci on PD 4. The presylvian and cruciate sulci emerged by PD 10, resulting in convolutions of gyri in the rostral half of the cerebrum. The caudal half of the cerebrum was infolded by the emergence of the pseudosylvian sulcus and the rhinal fissure by PD 10, and the caudal suprasylvian and lateral sulci by PD 21. The emergence of those sulci allowed a gyration in the caudal half of the cerebrum. Sexual differences in sulcation were detected by a more distinct convolution of the visual cortex in males than in females on PD 90. Those results, therefore, suggest that the ferret cerebrum experiences cortical maturation with sulcation and gyration in a rostrocaudal gradient manner. The present paper provides neuroanatomic references for normal development of cerebral sulci and gyri in both sexes of ferrets.

本研究旨在阐明雪貂发育中的大脑的脑沟和脑回模式。虽然大脑半球的脑重和额枕长度在出生后第42天达到稳定，但大脑宽度在前端区域于出生后第21天达到稳定，随后在后端区域于出生后第42天达到稳定。雪貂的大脑在出生后第4天就已经呈现出具有冠状沟和前端外侧沟凹陷的卷曲表面。在出生后第10天，出现了额叶前沟和十字沟，导致大脑前端一半出现脑回卷曲。在出生后第10天，由于假外侧沟和嗅裂的出现，以及在出生后第21天由于后端外侧沟和侧沟的出现，大脑后端一半发生内折。这些脑沟的出现使得大脑后端一半出现脑回。在出生后第90天，在脑沟方面检测到性别差异，雄性的视觉皮层卷曲比雌性更明显。因此，这些结果表明雪貂大脑以从前到后的梯度方式经历伴有脑沟和脑回的皮质成熟过程。本文为雪貂两性大脑脑沟和脑回的正常发育提供了神经解剖学参考。