Spinal control of penile erection

Rampin, Olivier; Bernabé, Jacques; Giuliano, François

doi:10.1007/bf01275150

Cited by 66 publications

(23 citation statements)

References 165 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Activation of such stretch receptors triggers reflex activation of motor neurons that innervate the ischiocavernosus and bulbospongiosus muscles, resulting in sufficient rigidity for intromission and ejaculation. That the lower spinal cord may contain the neural networks responsible for reflexive erections elicited by stimulation of afferent receptors in the penis is indicated by the presence of erectile responses in animals or humans with suprasacral spinal lesions (36). One model for the mode of action of MC4R agonists, as depicted in Fig.…”

Section: Discussionmentioning

confidence: 99%

A role for the melanocortin 4 receptor in sexual function

Ploeg

Martin

Howard

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

281

207

View full text Add to dashboard Cite

By using a combination of genetic, pharmacological, and anatomical approaches, we show that the melanocortin 4 receptor (MC4R), implicated in the control of food intake and energy expenditure, also modulates erectile function and sexual behavior. Evidence supporting this notion is based on several findings: (i) a highly selective nonpeptide MC4R agonist augments erectile activity initiated by electrical stimulation of the cavernous nerve in wild-type but not Mc4r-null mice; (ii) copulatory behavior is enhanced by administration of a selective MC4R agonist and is diminished in mice lacking Mc4r; (iii) reverse transcription (RT)-PCR and non-PCR based methods demonstrate MC4R expression in rat and human penis, and rat spinal cord, hypothalamus, brainstem, pelvic ganglion (major autonomic relay center to the penis), but not in rat primary corpus smooth muscle cavernosum cells; and (iv) in situ hybridization of glans tissue from the human and rat penis reveal MC4R expression in nerve fibers and mechanoreceptors in the glans of the penis. Collectively, these data implicate the MC4R in the modulation of penile erectile function and provide evidence that MC4R-mediated proerectile responses may be activated through neuronal circuitry in spinal cord erectile centers and somatosensory afferent nerve terminals of the penis. Our results provide a basis for the existence of MC4R-controlled neuronal pathways that control sexual function.O ur understanding of the physiology and anatomy of erectile function has advanced considerably in recent years (1-4). Penile erection is a highly coordinated reflex that is subject to modulation at many levels of the neuraxis. Relaxation of smooth muscle fibers of erectile tissue and concomitant dilatation of the arterial supply in the penis produce penile erection. Activation of neurons in the sacral spinal cord triggers activity in the pelvic nerve and, subsequently, the cavernous nerve, which can lead to the release of mediators of vasorelaxation, including nitric oxide. These mediators modulate cyclic nucleotide levels resulting in Ca 2ϩ sequestration and relaxation of smooth muscle fibers of the corpora cavernosa and corpus spongiosum in the shaft of the penis to produce arterial dilatation, engorgement of the penis with blood, and tumescence. Erections can be triggered either by peripheral (tactile) or by central (visual, olfactory, auditory, or imaginative cues) activation of somatic pathways and, as such, are influenced by tonic and phasic activity in the lumbosacral spinal cord and the brain.Five melanocortin heterotrimeric GTP-binding protein (G protein)-coupled receptors have been identified as expressed in different tissues (5, 6). The functional role of each of these five melanocortin receptors is being defined. Rodent and human genetic and pharmacological evidence indicates that activation of melanocortin 4 receptor (MC4R) results in a lean phenotype, whereas inactivation of the MC4R results in obesity (7-10). Recent studies have demonstrated that MTII, a cyclic analogue of ␣-mel...

show abstract

Section: Discussionmentioning

confidence: 99%

A role for the melanocortin 4 receptor in sexual function

Ploeg

Martin

Howard

et al. 2002

Proc. Natl. Acad. Sci. U.S.A.

281

207

View full text Add to dashboard Cite

show abstract

“…[2][3][4][5][6] The role of the spinal system has been extensively described. 7 On the other hand, little is known about the supraspinal control, specifically about the role of the thalamus.…”

Section: Introductionmentioning

confidence: 99%

Deep brain stimulation of the thalamus can influence penile erection

et al. 2004

View full text Add to dashboard Cite

“…However, the limit of such dichotomy is represented by the spinal cord, that contains autonomic sympathetic and parasympathetic neurons, and that receives and integrates proerectile information from the periphery (represented by sensory information from the genitalia) and from supraspinal nuclei. 4 In turn, supraspinal nuclei (e.g. the paraventricular nucleus and the medial preoptic area of the hypothalamus) may be considered as supraspinal re¯ex centers, because they also receive information from sensory afferents from the genitalia.…”

Section: Introductionmentioning

confidence: 99%

Central noradrenergic control of penile erection

Giuliano

Rampin

2000

Int J Impot Res

View full text Add to dashboard Cite

Penile erection is completely dependent on commands from the central nervous system. Spinal centers controlling penile erection are located in the thoracolumbar and lumbosacral spinal cord. These centers are activated by information from the periphery and supraspinal nuclei so as to elicit penile erection in a variety of physiological contexts. A small number of nuclei including the locus coeruleus located in the pons sends noradrenergic ®bers to the forebrain and spinal cord, including those areas controlling penile erection. Recent morphological techniques such as in situ hybridization and autoradiography using radioligand binding permit investigation of the brain and spinal pathways utilizing alpha adrenoceptor subtypes. Furthermore, pharmacological experiments suggest a modulatory role for noradrenaline in the control of penile erection either in the brain or in the spinal cord. The most robust evidence is that central inhibition of alpha-2 adrenoceptors facilitates sexual function. Taken together, the data propose new directions in the physiological exploration of penile erection and the therapeutic approach of erectile dysfunction.

show abstract

Spinal control of penile erection

Cited by 66 publications

References 165 publications

A role for the melanocortin 4 receptor in sexual function

A role for the melanocortin 4 receptor in sexual function

Deep brain stimulation of the thalamus can influence penile erection

Central noradrenergic control of penile erection

Contact Info

Product

Resources

About