Smooth muscle of rabbit isolated aorta contains the NK-2 tachykinin receptor.
Neurokinin A, neurokinin B and substance P caused concentration-related contractions of rabbit isolated aorta with pD2 values of 8.1, 6.9, and 6.0, respectively. [D-Pro2, D-Trp7, 9]-substance P, a competitive tachykinin antagonist, had pA2 values of 5.3 against neurokinin A, 5.1 against neurokinin B and 5.2 against substance P indicating that tachykinin receptors mediated responses to the agonists. [pGlu5,MePhe8,-MeGly9]-substance P 5 - 11 (DiMe-C7), senktide and septide did not contract the aorta. It is concluded that of the known tachykinin receptors smooth muscle of the rabbit isolated aorta contains only the NK-2 type.
Constantine
J W
JW
Exploratory Medicinal Chemistry, Pfizer Central Research, Pfizer Inc., Groton, CT 06340.
Lebel
W S
WS
Woody
H A
HA
D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure; D005260:Female; D007700:Kinetics; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology / Q000648:ultrastructure*; D015288:Neurokinin A / Q000494:pharmacology; D015287:Neurokinin B / Q000494:pharmacology; D011817:Rabbits; D017981:Receptors, Neurotransmitter / Q000378:metabolism* / Q000502:physiology; D018039:Receptors, Tachykinin; D013373:Substance P / Q000031:analogs & derivatives / Q000494:pharmacology
D017981:Receptors, Neurotransmitter; D018039:Receptors, Tachykinin; D013373:Substance P; C032132:substance P, prolyl(2)-tryptophan(7,9)-; D015288:Neurokinin A; D015287:Neurokinin B