PHASE DEPENDENT DISCREPANCY IN MURINE VAGINAL MICRO-ENVIRONMENT: A CORRELATIVE ANALYSIS OF pH, GLYCOGEN AND SERUM ESTROGEN UPON EXPOSURE TO LAPATINIB DITOSYLATE
Keywords:
estrous cycle, vaginal pH, phenol red, glycogen, estrogen, correlation analysisAbstract
Objective: This present investigation was designed to correlate the Hydrogen-ion concentration of vaginal fluid with glycogen content and serum estrogen level during different phases of mice reproductive cycle. These parameters were compared with the control and treated animals to set off this factor in the field of reproductive toxicological studies.
Methods: Female Swiss Albino mice [6-8 w] with regular estrous cyclicity were separated out into two groups as control [only HPMC] and treated [lapatinib in HPMC] animals. The treatment was carried out consecutively for 21 d via oral gavage at a dose of 20 mg/kg/d. Estrous cycle, pH and glycogen content of vaginal fluid was monitored on daily basis. At the end of the experiment period, serum estrogen level was quantified by ELISA method.
Results: Significant changes were observed in diestrus index, estrogen, and glycogen content with respect to their reproductive phases. In particular, the higher variations, seen within and between groups in estrous phase, suggest the maximum inhibitory potential exhibited by the drug used, was due to the elevated expression of its receptors [EGFR] at the time of oocyte maturation and ovulation.
Conclusion: Even, a change by one pH unit may illustrate the difference between healthy and heavily infected vaginal flora. Although, the pH value of vaginal secretions is not routinely used and compared with other parameters in the toxicological studies. This present study has become the trend set for considering pH as a valuable tool in in vivo studies.
Keywords: Estrous cycle, Vaginal pH, Phenol red, Glycogen, Estrogen, Correlation analysis
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