The State of Reproductive Organs of Young and Aged Male Rats at the Prolong Administration of Letrozole and after its Withdrawal

Volume 4, Issue 5, October 2020     |     PP. 94-110      |     PDF (465 K)    |     Pub. Date: October 12, 2020
DOI:    207 Downloads     5990 Views  

Author(s)

Alexander G. Reznikov, Department of Endocrinology of Reproduction and Adaptation, V.P. Komisarenko Institute of Endocrinology and Metabolism, National Academy of Medical Sciences of Ukraine, Kyiv< Ukraine
Olga V. Sachynska, Department of Endocrinology of Reproduction and Adaptation, V.P. Komisarenko Institute of Endocrinology and Metabolism, National Academy of Medical Sciences of Ukraine, Kyiv< Ukraine
Lyubov I. Polyakova, Department of Endocrinology of Reproduction and Adaptation, V.P. Komisarenko Institute of Endocrinology and Metabolism, National Academy of Medical Sciences of Ukraine, Kyiv< Ukraine
Oksana A. Faliush, Department of Endocrinology of Reproduction and Adaptation, V.P. Komisarenko Institute of Endocrinology and Metabolism, National Academy of Medical Sciences of Ukraine, Kyiv< Ukraine
Alexander V. Yanishevskiy, Department of Endocrinology of Reproduction and Adaptation, V.P. Komisarenko Institute of Endocrinology and Metabolism, National Academy of Medical Sciences of Ukraine, Kyiv< Ukraine

Abstract
Aim.Study of the reproductive organs at long-term administration of letrozole, the steroid aromatase inhibitor, followed by its withdrawal in young male rats and ones with age-related involution of reproductive organs.Material and methods. The experiments were carried out on Wistar rats with an initial age of 5 months and 15 months, which have been gavaged by letrozole every other day at a dose of 1 mg/kg b. w for 3 months and then 2 months after its discontinuation. The blood plasma testosterone and estradiol levels were measured by immunoassays. The spermatozoa concentrations in epididymal washes were determined. The testicles and accessory sexual glands were weighed, and morphology of gonads and ventral prostate have been studied. The results of the study were compared with those of control animals of corresponding age. Results.As the result of letrozole treatment, the ratio of testosterone and estradiol levels in blood plasma of aged rats increased. The spermatozoa content in epididymis rose up by 28% at average. The histological study revealed functional activation of Leydig cells, a significant retardation of involutive changes of their number and morphology. Some Leydig cells demonstrated the signs of functional exhaustion. Letrozole exerted an increase of relative weights of the coagulation gland by an average of 40%, seminal vesicles by 31%, and ventral prostate by 33% compared with those of control animals. Two months after letrozolewithdrawal, there were no any signs of difference between letrozole-treated and control animals. In young rats, the effects of letrozole were almost not detectable. Conclusions.Letrozole administration to male rats with age-related involution of the reproductive system increases testosterone/estradiol ratio in blood plasma, the spermatozoa content in epididymises and the weights of androgen-dependent accessory sexual glands. This is accompanied by slowing down of age-related changes of the gonad and prostate gland morphology. Letrozole-induced reproductive effects are reversible.

Keywords
letrozole, reproductive organs, male, rats.

Cite this paper
Alexander G. Reznikov, Olga V. Sachynska, Lyubov I. Polyakova, Oksana A. Faliush, Alexander V. Yanishevskiy, The State of Reproductive Organs of Young and Aged Male Rats at the Prolong Administration of Letrozole and after its Withdrawal , SCIREA Journal of Medicine. Volume 4, Issue 5, October 2020 | PP. 94-110.

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