Harnish P P, Northington F K, DiStefano V, Banerjee S
J Pharmacol Exp Ther. 1986 Feb;236(2):464-9.
The i.v. administration of radiographic contrast media decreases cerebrospinal fluid (CSF) production as measured by negative pressure collection from the lateral ventricles of anesthetized dogs. Evidence suggests that adrenergic-mediated adenylate cyclase (AC) activity controls CSF production. AC activity was measured in membrane fractions of bovine and canine choroid plexus and rat heart and lung in the presence of various concentrations of the contrast agent sodium diatrizoate. A concentration-dependent inhibition of isoproterenol-stimulated AC activity by the contrast agent was observed in vitro. Specific binding of [3H]dihydroalprenolol to membrane fractions of bovine choroid plexus was also inhibited by sodium diatrizoate. An indication that the inhibition of choroidal AC activity by contrast media is significant in vivo was obtained by measuring CSF production in dogs. The inhibition of CSF production by sodium diatrizoate was reduced 50% when the contrast agent was administered during an i.v. infusion of isoproterenol (100 ng/kg/min). These results indicate that the mechanism of decreased CSF production by contrast media may involve inhibition of beta adrenergic-stimulated AC activity.
通过对麻醉犬侧脑室进行负压收集来测量，静脉注射放射造影剂会降低脑脊液（CSF）的生成。有证据表明，肾上腺素能介导的腺苷酸环化酶（AC）活性控制着脑脊液的生成。在存在不同浓度造影剂泛影酸钠的情况下，对牛和犬脉络丛以及大鼠心脏和肺的膜部分中的AC活性进行了测量。在体外观察到造影剂对异丙肾上腺素刺激的AC活性有浓度依赖性抑制作用。泛影酸钠也抑制了[3H]二氢阿普洛尔与牛脉络丛膜部分的特异性结合。通过测量犬的脑脊液生成，获得了造影剂在体内对脉络丛AC活性的抑制作用显著的证据。当在静脉输注异丙肾上腺素（100 ng/kg/分钟）期间给予造影剂时，泛影酸钠对脑脊液生成的抑制作用降低了50%。这些结果表明，造影剂降低脑脊液生成的机制可能涉及抑制β肾上腺素能刺激的AC活性。
