Open AccessTime‐dependent changes in cardiovascular function during copulation in male rats
Author(s) -
Terada Misao,
Matsumura Atsufumi,
Kromkhun Pudcharaporn,
Taniguchi Kazumi,
Sato Fumio,
Sakurai Fujiro,
Yokosuka Makoto,
Nagy Gyorgy M.,
Saito Toru R.
Publication year - 2009
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 - 10.1007/s12522-009-0009-x
Subject(s) - ejaculation , heart rate , medicine , endocrinology , blood pressure , autonomic nervous system , estrous cycle , sympathetic nervous system , circulatory system , adult male , sexual behavior , clinical psychology
Abstract Purpose Sudden cardiac death after ejaculation has been reported in humans and highlights the important relationship between sexual behavior and the heart. The rat is an extremely useful animal model for investigating reproductive function in male mammals. In this study, we examined the relationship between autonomic nervous system activity and the circulatory system during sexual behavior in male rats. Methods Male Wistar–Imamichi rats were exposed to female rats in estrous and heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and plasma noradrenaline (NA) and adrenaline (Ad) concentrations were measured by telemetry during copulation. Results The resting HR was 365.5 ± 18.4 beats/min (mean ± SE), which increased to 531.2 ± 21.1 beats/min at ejaculation and decreased to 404.6 ± 30.7 beats/min 1 min after ejaculation. At rest, SBP and DBP were 123.8 ± 6.6 and 81.5 ± 4.1 mmHg, respectively, which increased to 154.5 ± 5.9 and 112.1 ± 7.3 mmHg at ejaculation. Baseline plasma Ad and NA concentrations were 151.6 ± 32.0 and 248.5 ± 22.5 pg/ml, respectively, and these increased to 393.8 ± 89.9 and 792.7 ± 154.0 pg/ml at ejaculation, after which they decreased to resting levels. The rate of increase in NA at ejaculation differed significantly from that of Ad. Conclusions The load on the circulatory and autonomic nervous systems is controlled by a rapid decrease in HR and NA concentration immediately after ejaculation, such that the male rat is prepared for the next copulation.