Abstract

The paraventricular nucleus (PVN) of the hypothalamus, which is considered to be a centre for autonomic regulation, has been shown to exhibit physiological and functional sex differences. It is involved in numerous functions, from stress to the appetite, body energy balance, blood pressure, heart rate and sexual activity, including penile erection [1], and is characterised by a very complex architecture. OXT is produced chiefly by magnocellular neurosecretory cells in the PVN and supraoptic nucleus of the hypothalamus and released into the blood from the axon terminals in the neurohypophysis and into the surrounding neuropil from magnocellular dendrites [2,3]. The principal functions attributed to OXT are involved in the regulation of reproductive functions including parturition, milk ejection, and sexual and maternal behaviour in females, so called a feminine hormone (for review, see Ref. [4] ). On the other hand, it is well accepted that a group of OXT-ergic neurones originating in the PVN and projecting to extrahypothalamic areas (e.g., hippocampus, medulla oblongata and spinal cord) control penile erection and sexual behaviour in male rats [5]. It has been reported that OXT positively impacted on a number of components of sexual function, including libido, erection, and orgasm in men [6-8]. The intracerebroventricular administration of OXT also induced a dose-dependent increase in the number of penile erections and yawning episodes in male rats, suggesting a physiological role of hypothalamic OXT in the regulation of such responses [9]. Because penile erection and yawning induced by either OXT or apomorphine in rats were antagonised in a dose-dependent manner by pre-treatment with OXT antagonists, dopamine may induce these responses by releasing OXT in vivo [9].

Highlights

  • Hirotaka Sakamoto*, Keita Satoh and Takumi Oti Laboratory of Neuroendocrinology, Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, Japan

  • The paraventricular nucleus (PVN) of the hypothalamus, which is considered to be a centre for autonomic regulation, has been shown to exhibit physiological and functional sex differences

  • It is well accepted that a group of OXT-ergic neurones originating in the PVN and projecting to extrahypothalamic areas control penile erection and sexual behaviour in male rats [5]

Read more

Summary

Introduction

Hirotaka Sakamoto*, Keita Satoh and Takumi Oti Laboratory of Neuroendocrinology, Ushimado Marine Institute (UMI), Graduate School of Natural Science and Technology, Okayama University, Japan Does oxytocin (OXT) release trigger ejaculation in men as well as parturition and milk ejection in women? It is well accepted that a group of OXT-ergic neurones originating in the PVN and projecting to extrahypothalamic areas (e.g., hippocampus, medulla oblongata and spinal cord) control penile erection and sexual behaviour in male rats [5].

Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.