Abstract:
Objective: To determine the effect of maternal hypothyroidism on the development of neurons in the motor
cortex of rat pups by using light microscopy.
Study Design: Laboratory-based experimental study.
Place and Duration of Study: The study was carried out in collaboration with the National Institute of Health
(NIH) Islamabad and the Department of Anatomy, Islamic International Medical College, Riphah International
University, Islamabad, Pakistan from March 2023 to May 2023.
Methods: In this study, 24 females and 12 male Sprague dawley rats were sorted into control and hypothyroid
groups. The control group received a standard diet and plain drinking water throughout the study. In contrast,
the hypothyroid group had 4.5mg of propylthiouracil administered per rat per day, mixed into their drinking
water. This treatment started a week before mating and continued until three weeks after delivery. Once
successful mating was confirmed via vaginal plugs, gestation proceeded, and newborn pups were born after
three weeks, having full access to maternal lactation for 21 days. On the 22nd day after birth, dissection took
place, and the brains of the pups were carefully removed. Coronal sections of the motor cortex were then
obtained for subsequent examination.
Results: The control group displayed a typical pattern of neurogenesis, characterized by the normal structure of
cortical neurons. On the other hand, intracellular vacuolation, glial cell necrosis, and reduced Nissl rim
thickness were statistically significant in hypothyroid group which collectively pointed to atypical neurogenesis.
Conclusion: This study highlights the adverse effects of maternal hypothyroidism on the structural integrity of
cortical neurons. It focuses on increasing awareness and implementing thorough prenatal healthcare
strategies.
