Effect of a gel containing pilocarpine on vaginal atrophy in castrated rats.
OBJECTIVE
To evaluate the effect of Carbopol gel formulations containing pilocarpine on the morphology and morphometry of the vaginal epithelium of castrated rats.


METHODS
Thirty-one female Wistar-Hannover rats were randomly divided into four groups: the control Groups I (n=7, rats in persistent estrus; positive controls) and II (n=7, castrated rats, negative controls) and the experimental Groups, III (n=8) and IV (n=9). Persistent estrus (Group I) was achieved with a subcutaneous injection of testosterone propionate on the second postnatal day. At 90 days postnatal, rats in Groups II, III and IV were castrated and treated vaginally for 14 days with Carbopol gel (vehicle alone) or Carbopol gel containing 5% and 15% pilocarpine, respectively. Next, all of the animals were euthanized and their vaginas were removed for histological evaluation. A non-parametric test with a weighted linear regression model was used for data analysis (p<0.05).


RESULTS
The morphological evaluation showed maturation of the vaginal epithelium with keratinization in Group I, whereas signs of vaginal atrophy were present in the rats of the other groups. Morphometric examinations showed mean thickness values of the vaginal epithelium of 195.10±12.23 μm, 30.90±1.14 μm, 28.16±2.98 μm and 29.84±2.30 μm in Groups I, II, III and IV, respectively, with statistically significant differences between Group I and the other three groups (p<0.0001) and no differences between Groups II, III and IV (p=0.0809).


CONCLUSIONS
Topical gel formulations containing pilocarpine had no effect on atrophy of the vaginal epithelium in the castrated female rats.
Universidade Federal do Piauí (UFPI), Escola de Farmácia, Teresina/PI, Brazil.
Cristina A
CA
de Sousa-Lages
Universidade Federal do Piauí (UFPI), Escola de Farmácia, Teresina/PI, Brazil.
Lívio P
LP
de Deus-Lages
Universidade Federal do Piauí (UFPI), Departamento de Ginecologia, Teresina/PI, Brazil.
Gabriela V
GV
de Sousa
Universidade Federal do Piauí (UFPI), Departamento de Ginecologia, Teresina/PI, Brazil.
Adinaide C
AC
de Moura-Leal
Universidade Federal do Piauí (UFPI), Departamento de Morfologia, Teresina/PI, Brazil.
Airton Mendes
AM
Conde
Universidade Federal do Piauí (UFPI), Departamento de Ginecologia, Teresina/PI, Brazil.
Danylo Rafhael
DR
Costa-Silva
Universidade Federal do Piauí (UFPI), Departamento de Ginecologia, Teresina/PI, Brazil.
Maria
M
da Conceição Barros-Oliveira
Universidade Federal do Piauí (UFPI), Departamento de Ginecologia, Teresina/PI, Brazil.
Carine Soares
CS
Borges
Universidade Federal do Piauí (UFPI), Postgraduate Program of the Northeast Network of Biotechnology (RENORBIO), Teresina/PI, Brazil.
Carla Solange
CS
Escórcio-Dourado
Universidade Federal do Piauí (UFPI), Postgraduate Program of the Northeast Network of Biotechnology (RENORBIO), Teresina/PI, Brazil.
Fabiane A
FA
Sampaio
Universidade Federal do Piauí (UFPI), Escola de Farmácia, Teresina/PI, Brazil.
Lívio C
LC
Cunha-Nunes
Universidade Federal do Piauí (UFPI), Escola de Farmácia, Teresina/PI, Brazil.|Universidade Federal do Piauí (UFPI), Postgraduate Program of the Northeast Network of Biotechnology (RENORBIO), Teresina/PI, Brazil.
Benedito B
BB
da-Silva
D000818:Animals; D001284:Atrophy / Q000188:drug therapy; D004848:Epithelium / Q000187:drug effects / Q000473:pathology; D005260:Female; D023421:Models, Animal; D018721:Muscarinic Agonists / Q000494:pharmacology*; D010862:Pilocarpine / Q000494:pharmacology*; D011897:Random Allocation; D017208:Rats, Wistar; D014621:Vagina / Q000187:drug effects / Q000473:pathology*
D018721:Muscarinic Agonists; D010862:Pilocarpine