FEATURES OF AGMATINE ANALGETIC EFFECT IN THE MODEL OF TONIC INFLAMMATORY PAIN

Abstract

Among the potential bipolar analgesics the imidazoline receptor stimulants are currently under consideration, their effect probably simulates the one of certain endogenous agonist, the most likely candidate for the role of which is a polyamine agmatine. Methods. In the experiment on nonlinear male rats during intraperitoneal introduction the researchers examined the agmatine sulphate effect on the severity of pain sensitivity and nociceptive threshold parameters on the model of tonic inflammatory pain. After taking the animals out of the experience the researchers using the method of high-performance liquid chromatography determined the agmatine content in different parts of the brain and in the cerebrospinal fluid. Results. Introduction of agmatine sulphate in the dose of 50, 100 and 200 mg/kg has reduced the severity of pain, mainly, at the tonic pain stage. Introduction of agmatine to the intact animals did not change the initial threshold of the temperature pain sensitivity but increased activity of «analgesia caused by pain.» After injection the drug accumulates in the spinal cord, brain and cerebrospinal fluid. Conclusions. Agmatine anti-algetic effect, probably, is due to its effect on the activity of different signaling mechanisms of the central nervous system, particularly the system of nitric oxide synthesis. The presence of the drug after intraperitoneal introduction in different parts of the brain indicates its ability to break the blood-brain barrier. This fact, along with the results of testing the agmatine biological activity allows to consider agmatineergic system of the brain as a potential target of analgesics.