Tyrosine kinases participate in alpha 1A-adrenoceptor-mediated vasoconstriction in perfused rat hindlimb.
OBJECTIVE
To determine whether or not tyrosine kinase is involved in the signal transduction of alpha 1A-adrenoceptors.


METHODS
Effects of various pharmacological probes on norepinephrine (NE)-induced vasopressor responses were determined in the perfused rat hindlimb.


RESULTS
The putative tyrosine kinase inhibitors, genistein, and tyrphostin, significantly inhibited the vasopressor responses induced by NE but not that induced by KCl. The protein-tyrosine-phosphatase inhibitor, sodium orthovanadate, selectively potentiated the vasopressor responses induced by NE. Neither genistein nor tyrphostin had effect on the contraction elicited by phorbol 12-myristate 13-acetate. In contrast, both genistein and tyrphostin attenuated the vasopressor responses evoked by NaF.


CONCLUSIONS
The genistein- and tyrphostin-sensitive tyrosine kinases participate in alpha 1A-adrenoceptor-mediated vasoconstriction in perfused rat hindlimb.
Zhu
W Z
WZ
Institute of Vascular Medicine, Third Hospital, Beijing Medical University, China.
Han
Q D
QD
D000818:Animals; D004791:Enzyme Inhibitors / Q000494:pharmacology; D019833:Genistein / Q000494:pharmacology*; D006614:Hindlimb / Q000098:blood supply; D010477:Perfusion; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D051381:Rats; D017208:Rats, Wistar; D018340:Receptors, Adrenergic, alpha-1 / Q000502:physiology*; D015398:Signal Transduction; D020032:Tyrphostins / Q000494:pharmacology; D014661:Vasoconstriction / Q000187:drug effects*
C547715:Adra1a protein, rat; D004791:Enzyme Inhibitors; D018340:Receptors, Adrenergic, alpha-1; D020032:Tyrphostins; D019833:Genistein; D011505:Protein-Tyrosine Kinases; D017027:Protein Tyrosine Phosphatases