Long J B, Kinney R C, Malcolm D S, Graeber G M, Holaday J W
Department of Medical Neurosciences, Walter Reed Army Institute of Research, Washington, DC 20307-5100.
Brain Res. 1987 Dec 15;436(2):374-9. doi: 10.1016/0006-8993(87)91683-0.
Radiolabeled microspheres were used to examine the effects of paralytic intrathecal doses of dynorphin A (Dyn A1-13) and Dyn A3-13 on rat brain and spinal cord blood flows and cardiac output. Dyn A1-13 produced significant dose-related reductions in blood flow to lumbosacral and thoracic spinal cord without altering cardiac output and blood flow to brain and cervical spinal cord. Naloxone failed to block these effects. Dyn A3-13, which lacks opioid activity, also significantly reduced blood flow in lumbosacral spinal cord. Thus, the paralytic effects of Dyn A in the rat may involve reductions in spinal cord resulting from non-opioid actions of Dyn A.
放射性标记微球被用于检测鞘内注射麻痹剂量的强啡肽A（Dyn A1-13）和Dyn A3-13对大鼠脑、脊髓血流及心输出量的影响。Dyn A1-13使腰骶部和胸段脊髓血流显著减少，且呈剂量相关性，同时不改变心输出量以及脑和颈段脊髓的血流。纳洛酮未能阻断这些效应。缺乏阿片样活性的Dyn A3-13也显著降低了腰骶部脊髓的血流。因此，强啡肽A在大鼠体内的麻痹作用可能涉及由其非阿片样作用导致的脊髓血流减少。
