The analgesic potential of intraventricular polymer-encapsulated adrenal chromaffin cells in a rodent model of chronic neuropathic pain.

Abstract

Adrenal chromaffin cells reportedly produce analgesic effects when implanted in the periaqueductal gray and the intrathecal space near the spinal cord. Chromaffin cells implanted in the cerebral ventricles may also produce analgesic effects, and the availability of the cerebral ventricles as a potential implant site could be advantageous for some patients. In fact, some of the first patients were implanted in the intraventricular site, even though the analgesic potential of that site had never been demonstrated. The present study was conducted to assess the analgesic potential of intraventricular, polymer-encapsulated calf adrenal chromaffin cells in the Bennett model. Sciatic nerve ligations produced substantial, long-lasting pain-related behaviors. However, there was no evidence that polymer-encapsulated adrenal chromaffin cells implanted in the cerebral ventricles produce analgesic effects in this model of chronic neuropathic pain.

Antinociceptive Effect of Intrathecal Microencapsulated Human Pheochromocytoma Cell in a Rat Model of Bone Cancer Pain

“…However, antinociception following chromaffin cell transplants produces controversial results in animal studies. For example, implantation of primary cultured human chromaffin cells has been observed in several chronic pain models [29,30], while bovine chromaffin cell grafts were shown to demonstrate no analgesic effect on acute or tonic pain in a rat formalin model [31,32]. It is suggested that the failure to produce antinociception might be due to inadequate amounts of grafted chromaffin cells, as well as low levels of met-enkephalin and catecholamines.…”