Femoral circulatory responses to lumbar nerve stimulation in developing swine.
Femoral circulatory responses to lumbar nerve stimulation in developing swine.
复制标题
发育中猪的股骨循环对腰神经刺激的反应。
DOI：
10.1152/ajpheart.1981.240.4.h505
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发表时间：
1981
期刊：
影响因子：
--
通讯作者：
Gootman,PM
中科院分区：
文献类型：
--
作者：
Buckley,NM;Brazeau,P;Frasier,ID;Gootman,PM
在51头发育中的猪（1日龄~3月龄）上，在戊巴比妥钠（10-30 mg/kg）麻醉下，测试了股循环对传出腰神经刺激的成熟反应。同时记录主动脉压、心率、股动脉和颈动脉血流（通过电磁流量传感器测量）。股动脉血管阻力计算为平均主动脉压/平均流量。横切腰神经纤维的交感神经链的最后一个神经节以下没有后，在一天的动物股阻力，但减少股阻力在猪1周龄及以上。在不同频率和强度组合下的传出腰神经刺激显示，1个月及以上猪的股循环反应中存在阿托品可阻断的血管扩张成分。在用酚妥拉明（0.25或0.5 mg/kg）阻断α-肾上腺素能受体后，仅在1个月及以上的动物中，在低频和高强度刺激腰神经期间发生股动脉血管舒张。乙酰胆碱（2微克IA）引起所有年龄段的股骨阻力下降。高频刺激（5 - 10 Hz）的血管收缩效应在所有年龄段都存在，并且具有年龄依赖性。这些实验的结果表明，在猪出生时的股循环的神经支配的功能活性血管收缩纤维，不提供一个滋补股阻力的影响，直到晚些时候在出生后的第一周。此外，虽然股血管胆碱能受体在出生时就可证实，但功能活跃的血管扩张纤维的成熟似乎延迟。
The maturation of femoral circulatory responses to efferent lumbar nerve stimulation was tested in 51 developing swine (1 day-3 mo old) under pentobarbital sodium anesthesia (10-30 mg/kg). Aortic pressure, heart rate, and femoral and carotid arterial flows (measured by electromagnetic flow transducers) were recorded simultaneously. Femoral vascular resistance was calculated as mean aortic pressure/mean flow. Transection of the lumbar nerve fibers below the last ganglion in the sympathetic chain did not after femoral resistance in day-old animals but decreased femoral resistance in swine 1 wk of age and older. Efferent lumbar nerve stimulation at various combinations of frequencies and intensities revealed an atropine-blockable vasodilator component in the femoral circulatory response in swine 1 mo of age and older. After alpha-adrenergic receptor blockade with phentolamine (0.25 or 0.5 mg/kg), femoral vasodilation occurred during low-frequency and -intensity stimulation of the lumbar nerve only in animals 1 mo of age and older. Acetylcholine (2 micrograms ia) caused a decrease in femoral resistance at all ages. Vasoconstrictor effects of high-frequency stimulation (5-10 Hz) were present at all ages and were age dependent. The results of these experiments suggest that the femoral circulation in swine at birth in innervated by functionally active vasoconstrictor fibers, which do not provide a tonic influence on femoral resistance until late in the first postnatal week. Furthermore, although femoral vascular cholinergic receptors are demonstrable at birth, there appears to be a delay in the maturation of functionally active vasodilator fibers.