Int J Anat Res 2019, 7(3.3):6929-33. ISSN 2321-4287 6929 Original Research Article THE IMMUNOHISTOCHEMICAL LOCALIZATION OF BAX IN THE BRAIN OF HYPOTHYROID NEONATE DURING MATERNAL MELATONIN INTAKE Mariyah Hidayat * 1 , Ihtisham Haider 2 , Abdullah Khurram 3 , Khalid P. Lone 4 . ABSTRACT Address for Correspondence: Dr Mariyah Hidayat, Associate Professor, Department of Anatomy, Rahbar Medical and Dental College, Lahore, Pakistan. E-Mail: drmariyah.hidayat@gmail.com Objective: To immunohistochemically localize Bax proteins in pyramidal cells of cerebral cortex in hypothyroid neonates and to observe the effect of melatonin on these cells. Study Design: Randomized controlled trial. Place and duration of study: Animal House and Anatomy Department at University of Health Sciences, Lahore. Material and Methods: Nine female wistar rats were randomly divided equally into three groups, including control(A), propylthiouracyl(B), melatonin treated propylthiouracyl (C) group and allowed to conceive. Medication was given throughout pregnancy and lactation. After delivery, 10 neonatal rats from each group were sacrificed on 22nd day of life and blood samples were immediately collected from the cardiac region for evaluating serum levels of TSH. The freshly extracted brains were immediately immersed in neutral buffered formalin for 3 weeks and later further processed. 3 m thick sections were sliced from cerebrum, deparaffinized and rehydrated, then washed in phosphate buffered saline and subsequently treated with primary and secondary antibodies. Results: PTU group had significant number of pyramidal neurons in cerebral cortex showing signs of apoptosis, whereas melatonin treated group showed reversal of these signs. Moreover, on serum analysis, the pups of dams taking PTU were severely hypothyroid whereas melatonin treated pups showed significant restoration of serum TSH levels. Conclusion: Melatonin preserves the structure and function of pyramidal neurons of cerebral cortex of neonates if ingested by hypothyroid mothers during gestation and lactation. KEY WORDS: Melatonin, Propylthiouracyl, hypothyroidism, thyroid stimulating hormone, anti-bax antibodies. INTRODUCTION International Journal of Anatomy and Research, Int J Anat Res 2019, Vol 7(3.3):6929-33. ISSN 2321-4287 DOI: https://dx.doi.org/10.16965/ijar.2019.259 Access this Article online Quick Response code International Journal of Anatomy and Research ISSN (E) 2321-4287 | ISSN (P) 2321-8967 https://www.ijmhr.org/ijar.htm DOI-Prefix: https://dx.doi.org/10.16965/ijar DOI: 10.16965/ijar.2019.259 *1 Associate Professor, Department of Anatomy, Rahbar Medical and Dental College, Lahore, Pakistan. 2 Research student at University of Health Sciences, Lahore, Pakistan. 3 Teaching and research fellow, Department of Anatomy, University of Health Sciences, Lahore, Pakistan. 4 Professor, Department of Physiology & Cell Biology, University of Health Sciences, Lahore, Pakistan. Received: 21 Jun 2019 Peer Review: 21 Jun 2019 Revised: None Accepted: 19 Aug 2019 Published (O): 05 Sep 2019 Published (P): 05 Sep 2019 Journal Information ICV for 2016 90.30 Article Information gestation [1]. Newborns which remain undiagnosed after birth or are treated incompletely for hypothyroidism Maternal hypothyroidism is significantly dam- aging for development of the fetus throughout 