neuropore

Neuropore is an embryological term referring to one of two openings at the ends of the developing neural tube during neurulation. The neural tube forms from the neural plate and gives rise to the brain and spinal cord; the neuropores provide temporary communication between the neural tube and the amniotic cavity.

There are two neuropores: the anterior (rostral) neuropore at the future head end and the posterior (caudal) neuropore at the tail end. Closure of these openings occurs as the neural tube forms, with the rostral neuropore typically closing around day 25 of gestation and the caudal neuropore around day 27–29 in humans. Closure generally proceeds from the middle of the neural tube outward toward the ends.

Failure of neuropore closure can lead to neural tube defects. Inadequate closure of the rostral neuropore can result in anencephaly or related cranial defects, while failure of the caudal neuropore to close can cause spinal dysraphism such as spina bifida. Protective factors, most notably folic acid intake before conception and during early pregnancy, reduce the risk of neural tube defects in many populations.

Etymology of the term combines “neuro-” (nerve or nervous system) with “pore,” referring to the openings in the neural tube. Neuropores are a brief, transient feature of early human development and are not present after the neural tube has fully closed.