Spinal proerectile effect of oxytocin in  anesthetized rats

The spinal cord contains the neural network that controls penile erection. This network is activated by information from peripheral and supraspinal origin. We tested the hypothesis that oxytocin (OT), released at the lumbosacral spinal cord level by descending projections from the paraventricular nucleus, regulated penile erection. In anesthetized male rats, blood pressure and intracavernous pressure (ICP) were monitored. Intrathecal (it) injection of cumulative doses of OT and the selective OT agonist [Thr4,Gly7]OT at the lumbosacral level elicited ICP rises whose number, amplitude, and area were dose dependent. Thirty nanograms of OT and one-hundred nanograms of the agonist displayed the greatest proerectile effects. Single injections of OT also elicited ICP rises. Preliminary injection of a specific OT-receptor antagonist, hexamethonium, or bilateral pelvic nerve section impaired the effects of OT injected it. NaCl and vasopressin injected it at the lumbosacral level and OT injected it at the thoracolumbar level or intravenously had no effect on ICP. The results demonstrate that OT, acting at the lumbosacral spinal cord, elicits ICP rises in anesthetized rats. They suggest that OT, released on physiological activation of the PVN in a sexually relevant context, is a potent activator of spinal proerectile neurons.

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Does Motor Learning Occur in the Spinal Cord?

The Neuroscientist ◽

10.1177/107385849700300510 ◽

1997 ◽

Vol 3 (5) ◽

pp. 287-294 ◽

Cited By ~ 47

Author(s):

V. Reggie Edgerton ◽

Roland R. Roy ◽

Ray De Leon Niranjala Tillakaratne ◽

John A. Hodgson

Keyword(s):

Spinal Cord ◽

Motor Task ◽

Lumbar Spinal Cord ◽

Lumbosacral Spinal Cord ◽

Patterns Of Use ◽

The Neural Network ◽

The Central Nervous System ◽

Network Plasticity ◽

Lumbar Spinal ◽

The Brain

It is becoming clear that the plasticity of the sensory-motor networks of the adult mammalian lumbosacral spinal cord is much greater than and is more dependent on the specific patterns of use than has been previously assumed. Using a wide variety of experimental paradigms in which the lumbar spinal cord is isolated from the brain, it has been shown that the lumbosacral spinal cord can learn to execute stepping or standing more successfully if that specific task is practiced. It also appears that the sensory input associated with the motor task and/or the manner in which it is interpreted by the spinal cord are important components of the neural network plasticity. Early evidence suggests that several neurotransmitter systems in the spinal cord, to include glycinergic and GABAergic systems, adapt to repetitive use. These studies extend a growing body of evidence suggesting that memory and learning are widely distributed phenomena within the central nervous system. NEUROSCIENTIST 3:287–294, 1997

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Activation of galanin and cholecystokinin receptors in the lumbosacral spinal cord is required for ejaculation in male rats

European Journal of Neuroscience ◽

10.1111/ejn.13515 ◽

2017 ◽

Vol 45 (6) ◽

pp. 846-858 ◽

Cited By ~ 6

Author(s):

Natalie Kozyrev ◽

Lique M. Coolen

Keyword(s):

Spinal Cord ◽

Male Rats ◽

Lumbosacral Spinal Cord ◽

Cholecystokinin Receptors

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Activation of Mu or Delta Opioid Receptors in the Lumbosacral Spinal Cord Is Essential for Ejaculatory Reflexes in Male Rats

PLoS ONE ◽

10.1371/journal.pone.0121130 ◽

2015 ◽

Vol 10 (3) ◽

pp. e0121130 ◽

Cited By ~ 13

Author(s):

Natalie Kozyrev ◽

Lique M. Coolen

Keyword(s):

Spinal Cord ◽

Opioid Receptors ◽

Male Rats ◽

Lumbosacral Spinal Cord ◽

Delta Opioid Receptors

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Role of spinal α1-adrenoceptor subtypes in the bladder reflex in anesthetized rats

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.2001.280.5.r1414 ◽

2001 ◽

Vol 280 (5) ◽

pp. R1414-R1419 ◽

Cited By ~ 26

Author(s):

Mitsuharu Yoshiyama ◽

William C. De Groat

Keyword(s):

Spinal Cord ◽

Afferent Input ◽

Bladder Pressure ◽

Contraction Amplitude ◽

Lumbosacral Spinal Cord ◽

Anesthetized Rats ◽

Bladder Contraction ◽

Transurethral Catheter ◽

Bladder Activity

The contribution of different subtypes of α1-adrenoceptors in the lumbosacral spinal cord to the control of the urinary bladder was examined in urethane-anesthetized rats. Bladder pressure was recorded via a transurethral catheter under isovolumetric conditions. Drugs were administered intrathecally at the L6-S1segmental level of spinal cord. RS-100329 (an α1A-antagonist) in doses of 25, 50, and 100 nmol significantly decreased bladder-contraction amplitude by 38%, 52%, and 95%, respectively, whereas (+)-cyclazosin (an α1B-antagonist) significantly decreased bladder-contraction amplitude (48% reduction) only in a 50-nmol but not a 100-nmol dose. Fifty nanomoles of RS-100329 and (+)-cyclazosin increased bladder-contraction frequency by 54% and 44%, respectively. BMY7378 (an α1D-antagonist), in doses of 25, 50, and 100 nmol, did not change bladder activity. These studies suggest that reflex-bladder activity is modulated by two types of spinal α1-adrenergic mechanisms: 1) α1A- or α1B-inhibitory control of the frequency of voiding reflexes presumably mediated by an alteration in the processing of bladder afferent input and 2) α1A-facilitatory modulation of the descending efferent limb of the micturition-reflex pathway. Spinal α1D-adrenoceptors do not appear to have a significant role at either site.

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