1.  Samreen Memon 2. Muhammad Yaqoob Shahani 3. Umbreen Bano 

4. Shazia Begum Shahani

1. Assoc. Prof. of Anatomy, LUM&HS, Jamshoro, Sindh 2 & 3. Lecturers of Anatomy, LUM&HS, Jamshoro, Sindh

4. Asstt. Prof. of Anatomy, Indus Medical College Tando Mohammad Khan, Sindh

ABSTRACT

Objective: To detect the possible teratogenic effects of various concentrations of retinoic acid (RA), in chick cardiac cells cultured in micromass culture.

Study Design: Experimental study

Place and Duration of Study: This study was carried out at the University of Nottingham, UK on chick embryonic hearts for a period of six months from Jan. 2010 to June 2010.

Materials and Methods: Embryonic hearts were dissected from 5 day old white leghorn chick embryos to produce a cardiac cell suspension in DMEM culture medium. Cells were either exposed to culture medium or vehicle only or to different concentrations of retinoic acid ranging from1 μM to 100 μM.  End points for cellular differentiation were observational scores at 24, 48 and 144 h following explantation. Cell viability was established with resazurin and kenacid blue assays. Statistical analysis of the results was via one way ANOVA and Kruskal Wallis tests and Pvalue < 0.05 was considered significant. 

Results: Retinoic acid significantly reduced cellular differentiation at and above 1 μM (P value < 0.05), at concentrations 50 μM and above no single focus was observed to be beating.  The resazurin assay for viability showed decreasing viability of cardiac cells with increasing concentrations of retinoic acid.  Same trend was observed with kenacid blue assay which determined the overall protein content.  However the cells exposed to only culture medium or vehicle did not show significant differences in terms of viability, protein content and beating ability.

Conclusion: The potential of retinoic acid as teratogen is proved in this in vitro study and it is recommended that the pregnant ladies should avoid the use of these drugs during early developmental period.

Key Words: Chick Embryonic Hearts, Micromass Culture, Retinoic Acid