Araki H, Su C, Lee T J
J Pharmacol Exp Ther. 1982 Jan;220(1):49-55.
The effect of sympathetic denervation on the sensitivity of the rabbit ear and basilar arteries and the cat middle cerebral artery to vasoactive agents was examined in relation to the functional significance of the innervation. Fourteen days after superior cervical ganglionectomy, the catecholamine fluorescence disappeared and the norepinephrine content drastically decreased and transmural nerve stimulation ceased to elicit any response in all these arteries. In the rabbit ear artery, denervation resulted in a significant leftward shift of dose-response curves for norepinephrine (8.2-fold), serotonin (7.7-fold), histamine (2.9-fold) and potassium (1.2-fold). In contrast, there was no significant shift of dose-response curves to these drugs in the rabbit basilar and cat middle cerebral arteries. These results indicate that after chronic superior cervical ganglionectomy, postjunctional supersensitivity developed in the rabbit ear artery, but no pre- or postjunctional supersensitivity occurred in the rabbit basilar and cat middle cerebral arteries. The difference may be in part attributable to the reported closer synaptic cleft distance of the sympathetic nerve terminals in the ear than in the cerebral arteries examined. These results further suggest that the sympathetic adrenergic nerve exerts a tonic influence over the rabbit ear artery, but little or none in normal cerebral blood vessels.
研究了交感神经去支配对兔耳动脉、基底动脉以及猫大脑中动脉对血管活性物质敏感性的影响，并探讨了其神经支配的功能意义。颈上神经节切除术后14天，儿茶酚胺荧光消失，去甲肾上腺素含量急剧下降，在所有这些动脉中，经壁神经刺激不再引起任何反应。在兔耳动脉中，去神经支配导致去甲肾上腺素（8.2倍）、5-羟色胺（7.7倍）、组胺（2.9倍）和钾（1.2倍）剂量反应曲线显著左移。相比之下，兔基底动脉和猫大脑中动脉对这些药物的剂量反应曲线没有显著移位。这些结果表明，慢性颈上神经节切除术后，兔耳动脉出现了节后超敏反应，但兔基底动脉和猫大脑中动脉未出现节前或节后超敏反应。这种差异可能部分归因于所报道的耳中交感神经末梢的突触间隙距离比所检查的脑动脉更近。这些结果进一步表明，交感肾上腺素能神经对兔耳动脉有紧张性影响，但对正常脑血管影响很小或没有影响。
