ABSTRACT
Objective To investigate the effectiveness of treating postherpetic neuralgia (PHN) by intradermal drug injection.Methods Ten rabbits of both sexes weighing 2.3-2.8 kg were anesthetized with intravenous urethane 1.5 g/kg. In group A (n = 5) 30% horseradish peroxidase(HRP) 500 ?l and in group B (n = 5) 1%-2% fluorescent nuclear yellow (NY) 500?l were injected intradermally at 6-8 points along the both sides of spine in the scapula region. After 48-72 h the animals were sacrificed and C4 -T10 spinal ganglia, cervical and thoracic sympathetic ganglia and celiac ganglia were harvested for identification of labeled neurocytes. Results Labeled neurocytes were found in C4-T10 spinal ganglia, cervical and thoracic sympathetic ganglia and celiac ganglia. There were more labeled neurocytes in the C6-T8 spinal ganglia. There were more labeled neurocytes in the sympathetic ganglia than in the spinal ganglia. The distribution of fluorescent labeled neurocytes corresponded to neurocytes labeled by HRP method. At the same segment there were more fluorescent labeled neurocytes than neurocytes labeled by HRP. Conclusion There is an ascending axoplasma streaming channel from nerver ending to the neurocytes in the ganglion as shown by morphological study and the good therapeutic effect of intradermal drug injection in the treatment of PHN may be related to this channel.