Sasa M, Munekiyo K, Igarashi S, Takaori S
Jpn J Pharmacol. 1976 Oct;26(5):519-25. doi: 10.1254/jjp.26.519.
Effects of alpha- and beta-adrenergic blocking agents applied into the lateral ventricle were studied on the relay neuron in the rostral part of spinal trigeminal nucleus (STN) of cats. Conditioning stimulation of the locus coeruleus (LC) and sensory cortex (SC) inhibited the orthodromic spike generation in STN relay neuron without affecting the antidromic spike, as already reported, and re-confirmed herein. The LC-induced inhibition of orthodromic spike was significantly reduced by intraventricular administration of beta-blockers, MJ 1999 (5 mg) and propranolol (0.5 mg), while the SC-induced inhibition of orthodromic one was not modified by the beta-blockers. The antidromic spike in STN relay neuron per se remained unaffected by these treatments. Intraventricular administration of alpha-blockers such as phentolamine and phenoxybezamine produced no alterations of the LC- and SC-induced inhibition of orthodromic spike. As the beta-blockers produced a selective antagonism, noradrenaline originating in LC probably acts as an inhibitory transmitter on the STN relay neuron and is mediated by beta-receptor.
研究了将α-和β-肾上腺素能阻断剂注入猫的侧脑室后，对其三叉神经脊束核（STN）吻侧部中继神经元的影响。如之前报道并在此再次证实的那样，对蓝斑（LC）和感觉皮层（SC）进行条件刺激会抑制STN中继神经元的顺向动作电位发放，而不影响逆向动作电位。经脑室注射β-阻断剂MJ 1999（5毫克）和普萘洛尔（0.5毫克）后，LC诱导的顺向动作电位抑制作用显著减弱，而SC诱导的顺向动作电位抑制作用未被β-阻断剂改变。这些处理本身对STN中继神经元的逆向动作电位没有影响。经脑室注射酚妥拉明和酚苄明等α-阻断剂，不会改变LC和SC诱导的顺向动作电位抑制作用。由于β-阻断剂产生了选择性拮抗作用，源自LC的去甲肾上腺素可能作为一种抑制性递质作用于STN中继神经元，并由β-受体介导。
