Olanzapine during lactation: impact on testicular morphometry and endocrine parameters in adult wistar rats

Olanzapine (OLZ) is an antipsychotic medication used to treat postpartum psychiatric symptoms. It aimed to evaluate the effects of administering OLZ to lactating rats on testicular parameters of adult Wistar rats. Mothers received 2.5, 5 or 10 mg/kg until weaning. Adult male rats showed decrease in body weight, weight of testes, epididymis, prostate, seminal gland and gonadosomatic index when higher doses of OLZ were administered. Testicular volumetric parameters, as well as the length of seminiferous tubules, were also reduced in animals treated with the highest doses of OLZ. The diameter of the seminiferous tubules and the height of the seminiferous epithelium were reduced. There was also a relevant decrease in the population of Sertoli cells and a relevant reduction in the volume of individual Leydig cells. Histopathological analysis of the testes showed lesions compatible with testicular degeneration in rats treated with the highest dose of OLZ. There was a significant reduction in plasma testosterone levels in all treatments. It is noted, therefore, that the adverse impact on the testes of the highest doses of the drug during the neonatal period persisted into adulthood, with the dose of 2.5 mg/kg of OLZ proving to be safer than the others.