RT Journal Article
SR Electronic
T1 Endogenous Opioid Release After Orgasm in Man: A Combined PET/Functional MRI Study
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP jnumed.123.265512
DO 10.2967/jnumed.123.265512
A1 Jern, Patrick
A1 Chen, Jinglu
A1 Tuisku, Jouni
A1 Saanijoki, Tiina
A1 Hirvonen, Jussi
A1 Lukkarinen, Lasse
A1 Manninen, Sandra
A1 Helin, Semi
A1 Putkinen, Vesa
A1 Nummenmaa, Lauri
YR 2023
UL http://jnm.snmjournals.org/content/early/2023/07/13/jnumed.123.265512.abstract
AB The endogenous μ-opioid receptor (MOR) system plays a key role in the mammalian reward circuit. Human and animal experiments suggest the involvement of MORs in human sexual pleasure, yet this hypothesis currently lacks in vivo support. Methods: We used PET with the radioligand [11C]carfentanil, which has high affinity for MORs, to quantify endogenous opioid release after orgasm in man. Participants were scanned once immediately after orgasm and once in a baseline state. Hemodynamic activity was measured with functional MRI during penile stimulation. Results: The PET data revealed significant opioid release in the hippocampus. Hemodynamic activity in the somatosensory and motor cortices and in the hippocampus and thalamus increased during penile stimulation, and thalamic activation was linearly dependent on self-reported sexual arousal. Conclusion: Our data show that endogenous opioidergic activation in the medial temporal lobe is centrally involved in sexual arousal, and this circuit may be implicated in orgasmic disorders.