Moldow R L, Kastin A J, Hollander C S, Coy D H, Sandman C A
Brain Res Bull. 1981 Dec;7(6):683-6. doi: 10.1016/0361-9230(81)90118-0.
beta-endorphin-like immunoreactivity was measured by radioimmunoassay in the brains of adult rats treated neonatally with beta-endorphin, naloxone, or vehicle. After treatment with beta-endorphin, the decreases observed in beta-endorphin-like immunoreactivity in the hypothalamus, pineal, midbrain, pons-medulla, hippocampus, striatum, frontal cortex, occipital cortex, and posterior cortex were highly significant but the 23% decrease in the thalamus was not significantly different from that of control rats. Neonatal administration of naloxone only resulted in a significant decrease in beta-endorphin-like immunoreactivity in the hypothalamus. In contrast, no differences were discernible in content of either beta-endorphin-like immunoreactivity or ACTH-like immunoreactivity in the pituitary of rats treated with beta-endorphin, naloxone, or vehicle in the neonatal period. These same rats had shown an increased threshold to painful thermal stimulation by the tail-flick test after administration of either beta-endorphin or naloxone at birth. The results suggest that neonatally injected beta-endorphin may alter the levels of beta-endorphin-like immunoreactivity in rat brain as well as the response to pain.
通过放射免疫分析法测定了新生期用β-内啡肽、纳洛酮或赋形剂处理的成年大鼠大脑中的β-内啡肽样免疫反应性。用β-内啡肽处理后，下丘脑、松果体、中脑、脑桥-延髓、海马、纹状体、额叶皮质、枕叶皮质和后皮质中观察到的β-内啡肽样免疫反应性降低非常显著，但丘脑23%的降低与对照大鼠无显著差异。新生期给予纳洛酮仅导致下丘脑β-内啡肽样免疫反应性显著降低。相比之下，新生期用β-内啡肽、纳洛酮或赋形剂处理的大鼠垂体中，β-内啡肽样免疫反应性或促肾上腺皮质激素样免疫反应性的含量均无明显差异。这些大鼠在出生时给予β-内啡肽或纳洛酮后，通过甩尾试验显示对疼痛热刺激的阈值增加。结果表明，新生期注射β-内啡肽可能会改变大鼠大脑中β-内啡肽样免疫反应性水平以及对疼痛的反应。
