Neuronal Damage In Brains Of First- And Second-Generation Pups Born To Hypothyroid Wistar Rats

OBJECTIVE: To study neuronal damage in brains of first and second-generation pups, born to hypothyroid Wistar rats.METHODS: Ten female adult Wistar rats, randomized into two equal groups-propylthiouracil (Group-P) and control (Group-C) were allowed to conceive. Group-P was given oral propylthiouracil throughout gestational period and ndweaning until 22 day. Nine offspring from group-C (C/FC) and group-P (P/FC) ndwere sacrificed on 22 day of life to collect blood and brain samples. The dams of group-P (group-PP) were allowed to conceive and continued with propylthiouracil treatment throughout gestation and weaning. Their nine ndoffsprings (PP/FC) were sacrificed on 22 day. Serum levels of triiodothyronine (T), thyroxine (T) and thyroid stimulating hormone (TSH) were measured. Brain 3 4 weight, apoptotic cell count (ACC) of Purkinje cells of cerebellar cortex and Pyramidal cells of hippocampus were documented.RESULTS: Mean TSH levels were 21 +/- 3.g/dl, 23.3 +/- 3.5.g/dl and 10 +/- 2.1.g/dl in P/FC, PP/FC and C/FC respectively (p = 0.003). Mean T was 31.7 +/- 1.2.g/dl, 4 30.3 +/- 1.3.g/dl and 36.3 +/- 0.9.g/dl in P/FC, PP/FC and C/FC respectively (p = 0.030). Mean brain weights was 1.21 +/- 0.21 mg, 1.20 +/- 0.41 mg and 1.42 +/- 0.01 mg group in P/FC, PP/FC and C/FC respectively (p > 0.05). The normal Pyramidal and Purkinje cell count was low in P/FC and PP/FC groups compared to C/FC group (p < 0.05). The ACC of Pyramidal and Purkinje cells was high in P/FC and PP/FC groups compared to C/FC group (p < 0.05).CONCLUSION: Maternal hypothyroidism adversely affected the morphology of Pyramidal and Purkinje cells by enhancing apoptosis, which increased further in second generation pups.