In Ovo Telmisartan Exposure and Developmental Consequences in Embryonic Life Stage of Gallus gallus.

Telmisartan, an antihypertensive drug, lowers blood pressure by blocking the angiotensin-II receptor subtype-1 (AT1). A few sporadic case studies reported adverse fetal effects of telmisartan in humans. Moreover, there is a scarcity of information from animal trials to assess its teratogenic potential. The purpose of this study is to assess the potential effects of telmisartan on embryonic development in chicks as a model. The drug was prepared in a sterile 0.9% normal saline solution (NSS) vehicle, and four different dosages of 0.0625, 0.125, 0.25, and 0.50 mg/egg were administered to the blastodiscs on each of the Hamburger and Hamilton (HH) stages 4, 7, 9, and 12. The developmental outcomes of all experimental embryos were assessed at HH stages 14, 19, and 24. Exposure to telmisartan resulted in syndromic development characterized by a wide range of morphological deformities in neural, optic, and otic development; abnormal looping of the heart; delayed angiogenesis; somitic anomalies; and incomplete body flexure. Telmisartan affected heart rate, body length, somite numbers, and area vasculosa in a dose- and stage-dependent manner. The results of this animal model experiment will help assess the teratogenic potential of telmisartan and will serve as a foundation for future research to uncover the mechanisms underlying telmisartan-induced developmental assault.