Comparison ofneurokinin A andsubstance Poncardiovascular andairway function inman

The airway and cardiovascular effects of intravenous neurokinin A (NKA) andsubstanceP(SP)werecomparedinsixnormalsubjects. BothSPandNKAincreasedskintemperature(SkT)andheartrate(HR),butSPwasmorepotentthanNKAbyfactorsof6and 20 respectively. No change in systolic blood pressure (BP) occurred with eitherpeptide,butdiastolicBPfellsignificantlywithSPinfusion. SPcausedbronchodilationandNKAbronchoconstriction. NKAand SP have differing physiological roles and mayactivate different receptorpopulations.Keywords tachykinins substanceP neurokinin A bronchoconstrictionvasodilation