Open AccessThe influence of psychological stress in early life on sexual maturation and sexual behavior in male and female rats
Author(s) -
Yano Kiyohito,
Matsuzaki Toshiya,
Iwasa Takeshi,
Mayila Yiliyasi,
Yanagihara Rie,
Tungalagsuvd Altankhuu,
Munkhzaya Munkhsaihan,
Tokui Takako,
Kamada Shuhei,
Hayashi Aki,
Masaki Rie,
Aoki Hidenori,
Tamura Kou,
Irahara Minoru
Publication year - 2020
Publication title -
reproductive medicine and biology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.005
H-Index - 22
eISSN - 1447-0578
pISSN - 1445-5781
DOI - 10.1002/rmb2.12313
Subject(s) - estrous cycle , sexual behavior , sexual maturity , preputial gland , sex organ , medicine , affect (linguistics) , psychology , physiology , sexual arousal , endocrinology , developmental psychology , biology , communication , genetics
Purpose We studied the influence of psychological stress during the early neonatal period on sexual maturation and sexual behavior in rats. Methods Neonatal male and female rats were divided into control (C) and maternal separation (MS) groups (n = 20‐24 per group). The pups in the MS groups were placed in isolation cages for 240 minutes/d from postnatal days 2‐11. Vaginal opening (VO) in females and preputial separation (PS) in males (indicators of sexual maturation) were monitored, as was the estrous cycle in females. Thereafter, sexual behavior was monitored twice at 13 and 15 weeks of age. Results As for sexual maturation, the onset of PS occurred significantly earlier in the MS group than in the C group, whereas the onset of VO did not differ between the groups. The length of the estrous cycle did not differ between the groups. The frequencies of sexual behaviors did not differ between the groups in either sex. Conclusions In conclusion, early‐life psychological stress induced by MS advanced sexual maturation in male rats, whereas it did not affect sexual maturation in female rats. On the other hand, early‐life psychological stress might not affect sexual behavior in adulthood in either sex.