Comparative effects of quinacrine and erythromycin in adult female rats: a nonsurgical sterilization study.
OBJECTIVE
To compare the efficacies of erythromycin and quinacrine for nonsurgical sterilization in rats. Quinacrine used for nonsurgical sterilization in women is mutagenic, and most clinical regimens have had a higher failure rate than surgical sterilization.


METHODS
This acute mammal study included five groups of rats assigned randomly and evaluated at two times after treatment.


METHODS
Adult female Sprague-Dawley rats.


METHODS
Five groups of female Sprague-Dawley rats (20 per group) were given 70 or 280 mg/kg of erythromycin lactobionate, 350 mg/kg of quinacrine hydrochloride, or vehicle control administered transcervically. Rats were mated 21 days later. Additional groups (n = 4 per group) were treated and killed 21 days later without mating.


METHODS
Fourteen days after mating, numbers of ovarian corpora lutea, total uterine implants, and embryos were evaluated. For unmated animals, uterine sections were examined for fibrosis and lumen closure.


RESULTS
Neither drug altered numbers of corpora lutea. Erythromycin decreased pregnancy rate and number of implantations (increased preimplantation loss) in a dose-related fashion. Quinacrine increased resorptions. Uterine pathology was more extensive and frequent in erythromycin-treated animals, with extent and severity increasing from 21 to 35+ days.


CONCLUSIONS
Erythromycin was more effective than quinacrine in preventing pregnancy.
Fail
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PA
Laboratory of Reproductive and Endocrine Toxicology, Research Triangle Institute, Research Triangle Park, North Carolina 27709, USA. patf@rti.org
Martin
P
P
Sokal
D
D
D000282:Administration, Intravaginal; D000818:Animals; D004305:Dose-Response Relationship, Drug; D010064:Embryo Implantation / Q000187:drug effects; D047108:Embryonic Development; D004917:Erythromycin / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000633:toxicity; D005069:Evaluation Studies as Topic; D005260:Female; D005313:Fetal Death; D011247:Pregnancy; D011796:Quinacrine / Q000494:pharmacology* / Q000633:toxicity; D051381:Rats; D017207:Rats, Sprague-Dawley; D013245:Sterilization, Reproductive / Q000379:methods*; D014599:Uterus / Q000187:drug effects / Q000473:pathology*
C010948:erythromycin lactobionate; D004917:Erythromycin; D011796:Quinacrine