objective(s): the present study investigated the effects of microinjection of histamine and histamine h1, h2, and h3 receptor antagonists, chlorpheniramine, ranitidine and thioperamide, respectively into the primary somatosensory cortex (psc) on inflammatory pain. material and methods: two stainless steel guide canulas were bilaterally implanted into the psc of anaesthetized rats. inflammator...