Spinal effects of oxytocin on uterine motility in anesthetized rats

被引:12
作者
Benoussaidh, A [1 ]
Maurin, Y [1 ]
Rampin, O [1 ]
机构
[1] INRA, F-78352 Jouy En Josas, France
关键词
urogenital; lumbosacral spinal cord; sexual reflexes;
D O I
10.1152/ajpregu.00117.2004
中图分类号
Q4 [生理学];
学科分类号
071003 ;
摘要
The rat uterus receives an innervation from the lumbosacral and thoracolumbar segments of the spinal cord. These segments receive descending oxytocinergic projections from the paraventricular nucleus of the hypothalamus. We tested the hypothesis that oxytocin regulates uterine motility through a spinal site of action. Oxytocin was administered in anesthetized female rats either intrathecally at the lumbosacral or thoracolumbar spinal cord levels or intravenously. Uterine activity was revealed by measuring changes of intrauterine pressure using an indwelling balloon placed in one caudal uterine horn. The uterus displayed a spontaneous activity characterized by intrauterine pressure rises, the frequency, amplitude, and duration of which were dependent on the stage of the estrous cycle. Oxytocin delivered at the lumbosacral level affected the frequency (during proestrus, estrus, and diestrus) and amplitude ( during proestrus and estrus) of uterine activity. During estrus, oxytocin delivered at the thoracolumbar level affected the frequency, amplitude, and duration of the intrauterine pressure rises. Intravenous oxytocin not only affected intrauterine pressure rises ( namely amplitude during proestrus and estrus and frequency and duration during estrus) but also increased the basal tone during estrus. The effects of lumbosacral oxytocin were partly mimicked by the oxytocin agonist [Thr(4), Gly(7)]-oxytocin blocked by the oxytocin receptor antagonist atosiban and by hexamethonium. Arginine vasopressin delivered at the lumbosacral level had no effect. These results support our hypothesis that oxytocin released by descending paraventriculo-spinal pathways and acting on spinal oxytocin receptors modulates the activity of the uterus. This regulation is cycle dependent.
引用
收藏
页码:R446 / R453
页数:8
相关论文
共 39 条
[31]   THE PARAVENTRICULAR NUCLEUS OF THE HYPOTHALAMUS - CYTOARCHITECTONIC SUBDIVISIONS AND ORGANIZATION OF PROJECTIONS TO THE PITUITARY, DORSAL VAGAL COMPLEX, AND SPINAL-CORD AS DEMONSTRATED BY RETROGRADE FLUORESCENCE DOUBLE-LABELING METHODS [J].
SWANSON, LW ;
KUYPERS, HGJM .
JOURNAL OF COMPARATIVE NEUROLOGY, 1980, 194 (03) :555-&
[32]   DISTRIBUTION OF OXYTOCIN-STAINED AND NEUROPHYSIN-STAINED FIBERS IN THE SPINAL-CORD OF THE RAT AND MONKEY [J].
SWANSON, LW ;
MCKELLAR, S .
JOURNAL OF COMPARATIVE NEUROLOGY, 1979, 188 (01) :87-106
[33]   IMMUNOHISTOCHEMICAL EVIDENCE FOR A NEUROPHYSIN-CONTAINING AUTONOMIC PATHWAY ARISING IN PARAVENTRICULAR NUCLEUS OF HYPOTHALAMUS [J].
SWANSON, LW .
BRAIN RESEARCH, 1977, 128 (02) :346-353
[34]  
TONER JP, 1986, J REPROD FERTIL, V78, P239, DOI 10.1530/jrf.0.0780239
[35]  
TRAURIG HH, 1993, NERVOUS CONTROL UROG, P103
[36]   Distribution of vasopressin and oxytocin receptors in the rat spinal cord: Sex-related differences and effect of castration in pudendal motor nuclei [J].
Tribollet, E ;
Barberis, C ;
Arsenijevic, Y .
NEUROSCIENCE, 1997, 78 (02) :499-509
[37]   Oxytocinergic innervation of autonomic nuclei controlling penile erection in the rat [J].
Véronneau-Longueville, F ;
Rampin, O ;
Freund-Mercier, MJ ;
Tang, Y ;
Calas, A ;
Marson, L ;
McKenna, KE ;
Stoeckel, ME ;
Benoit, G ;
Giuliano, F .
NEUROSCIENCE, 1999, 93 (04) :1437-1447
[38]   OXYTOCIN ADMINISTERED INTRATHECALLY PREFERENTIALLY INCREASES HEART-RATE RATHER THAN ARTERIAL-PRESSURE IN THE RAT [J].
YASHPAL, K ;
GAUTHIER, S ;
HENRY, JL .
JOURNAL OF THE AUTONOMIC NERVOUS SYSTEM, 1987, 20 (02) :167-178
[39]   Involvement of oxytocin in spinal antinociception in rats with inflammation [J].
Yu, SQ ;
Lundeberg, T ;
Yu, LC .
BRAIN RESEARCH, 2003, 983 (1-2) :13-22