The role of substance P in cerebral ischemia.

Tackykinins are involved in the inflammatory process of a large number of diseases. The role of the tachykinins in ischemic brain injury was evaluated by the serum levels of Substance P (SP), one of the most known tachykinins and detected by a competitive enzyme immunoassay. The study was performed in 15 human females and 3 human males with typical manifestation of complete stroke (12 cases) or transient ischemic attack (6 cases). The mean SP level in the serum of patients with transient ischemic attack (0.53+/-0.25 ng/ml) and of patients with complete stroke (0.31+/-0.14 ng/ml), showed significantly higher values than in controls (0.10+/-0.02 ng/ml). Moreover, in transient ischemic attack, the SP values were significantly higher than in cerebral complete stroke. But SP levels, based on the timings of classification of patients (i.e. before 12 hours: 0.34+/-0.15 ng/ml vs. 12 to 24 hours: 0.26+/-0.11 ng/ml) with brain injury, did not show any significant difference. Both values anyway were significantly higher than in controls. Our original results demonstrate the SP increase during cerebral ischemia. Further studies are necessary to verify if SP has an effective physiopathological role in the neurological ischemic damage, or if it is only a concomitant phenomenon. Our data, if confirmed, will be particularly important, not only to improve the knowledge of cerebral ischemic injury, but also for diagnosis and therapeutic approaches.

Cetirizine, a second-generation H1 antagonist, modulates Rantes and MCP-1 levels in allergic rhinitis.

Chemokines and their receptors are involved in several allergic diseases. We measured RANTES and MCP-1 levels in sera of allergic rhinitis patients, and also we evaluated the effect of cetrizine, a second-generation H1 antagonist, on these chemoattractant proteins. 15 subjects were studied (10 males and 5 females; mean age: 26.7 years). They were suffering from perennial or seasonal allergic rhinitis induced by Dermatophagoides pteronyssinus (8 patients) or by grasses (7 patients). RANTES and MCP-1 serum levels were detected with an enzyme immunoassay before and after two weeks of treatment with 10 mg of cetirizine daily, and again after two weeks of washout. Baseline serum levels of RANTES and MCP-1 chemokines were significantly higher (p < 0.02 and p = 0.007, respectively) in allergic patients than in the healthy control group. Cetirizine resulted in a significant decrease in RANTES (p < 0.02) and MCP-1 (p = 0.003) versus baseline values. There is an increase in RANTES and MCP-1 in allergic rhinitis, which is counteracted by cetirizine.