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Liquid-base cytology: a new method for oestral cycle study in Wistar's rats
Rand Randall Martins1, Ney Moura Lemos Pereira, Telma Maria Araújo Silva
1Faculdade de Farmácia, Departamento de Análises Clínicas e Toxicológicas da UFRN/CCS Natal-RN. randmartins@yahoo.com.br
Objectives:
The objective of this study was the standardization of a collection technique and staining in liquid-base that allies the pratical and cytological wealth, making possible a larger reproductibility and microscopic easiness.
Methods:
Female wistar rats (n = 20) were submitted to the daily vaginal collection in saline and fastened washed (ether/alcohol) and stained in suspension with a solution of Evans Blue 0.025%. The sample was pondered by centrifugation and observed under lens of 40 x.
Results:
The stained smears allowed clear differentiation of the phases of hormonal cycle (diestrus, proestrus, estrus and metestrus); besides the differentiation of the cellular types in relation to its maturation degree having as parameters the cellular size, nucleus/cytoplasm relationship (NCR) and ink reaction. The study demonstrated the existence of three basic cellular patterns: cells with low NCR, accentuated cyanophily and small size; cells with increment in NCR, cyanophilic loss and larger volume cytoplasmatic and without nuclei keratinization cells in squamous aspect.
Conclusion:
The staining of the material allowed, besides the cytological classification, the quantification possibility that would result in a perfected accompaniment of the cycle estrous.
