Hsieh J T, Liu S P, Hsieh C H, Lai M K, Cheng J T
Department of Urology, College of Medicine, National Taiwan University Hospital, Taipei, Republic of China.
Life Sci. 1998;63(15):PL221-9. doi: 10.1016/s0024-3205(98)00403-2.
We studied the neural regulation of seminal vesicles (SV) by determining the changes of intraluminal pressure of rat SV in response to an electric stimulation of the lesser splanchnic nerve (LSN). After pharmacological manipulation with neurotoxin, the contents of monoamines and their metabolites in SV were estimated. In rats receiving electric stimulation of the LSN, an increase of intraluminal pressure was obtained with a reduction of the serotonergic turnover rate in SV. An intraperitoneal injection of DSP-4 (100 mg/kg), the noradrenergic neurotoxin, into rats decreased the level of norepinephrine (NE) in SV significantly but did not influence this functional response. Also, the intraluminal pressure was lowered by an intrathecal injection of 6-OHDA (20 microg/rat) to denervate spinal monoaminergic nerves in rats although the contents of monoamines in SV were not changed. This indicates that noradrenergic neurotransmission appears unimportant in this regulation. The lowering of intraluminal pressure in rats by 6-OHDA is mainly related to an attenuation of dopaminergic neuroregulation from the decrease of turnover rate of DA. Otherwise, an intrathecal injection of 5,7-DHT (60 microg/rat) to abolish spinal serotonergic nerves did not influence the level of monoamines in SV but increased the intraluminal pressure indicating an involvement of inhibitory regulation from spinal serotonergic pathway. These results suggest that contraction by electric stimulation of the LSN in Wistar rat SV is mainly regulated by the dopaminergic nervous pathway and an inhibitory regulation of the serotonergic nervous pathway from spinal cord while the noradrenergic nervous system seems unimportant for this regulation.
我们通过测定大鼠精囊（SV）腔内压力对内脏小神经（LSN）电刺激的反应变化，研究了精囊的神经调节。在用神经毒素进行药理学操作后，对精囊中单胺及其代谢产物的含量进行了评估。在接受LSN电刺激的大鼠中，精囊腔内压力升高，同时精囊中血清素能周转率降低。向大鼠腹腔注射去甲肾上腺素能神经毒素DSP-4（100mg/kg）可显著降低精囊中去甲肾上腺素（NE）的水平，但不影响这种功能反应。此外，鞘内注射6-羟基多巴胺（6-OHDA，20μg/只大鼠）使大鼠脊髓单胺能神经去神经支配，尽管精囊中单胺含量未改变，但精囊腔内压力降低。这表明去甲肾上腺素能神经传递在这种调节中似乎并不重要。6-OHDA使大鼠精囊腔内压力降低主要与多巴胺能神经调节减弱有关，这是由于多巴胺周转率降低所致。否则，鞘内注射5,7-二羟色胺（5,7-DHT，60μg/只大鼠）以消除脊髓血清素能神经，并不影响精囊中单胺水平，但增加了精囊腔内压力，表明脊髓血清素能途径参与了抑制性调节。这些结果表明，Wistar大鼠精囊经LSN电刺激引起的收缩主要受多巴胺能神经通路调节，以及脊髓血清素能神经通路的抑制性调节，而去甲肾上腺素能神经系统在这种调节中似乎并不重要。
