Pyk2 mediates increased adrenergic contractile responses in arteries from DOCA-salt mice - VASOACTIVE PEPTIDE SYMPOSIUM.
BACKGROUND
The calcium-dependent proline-rich tyrosine kinase (Pyk2), a nonreceptor protein activated by tyrosine phosphorylation, links G protein-coupled receptors to vascular responses. We tested the hypothesis that enhanced vascular reactivity in DOCA-salt hypertensive mice are due to increased activation of Pyk2.


RESULTS
Aorta and small mesenteric arteries from DOCA-salt and uninephrectomized (UNI) male C57Bl/6 mice were used. Systolic blood pressure (mmHg) was higher in DOCA (126+/-3) vs. UNI (100+/-4) mice. Vascular responses to phenylephrine (1nM to 100muM) were greater both in aorta and small mesenteric arteries from DOCA-salt than UNI, but treatment with Tyrphostin A-9 (0.1muM, Pyk2 inhibitor) abolished the difference among the groups. Pyk2 levels, as well as phospho-Pyk2(Tyr402), paxillin and phospho-paxillin(Tyr118) were increased in DOCA-salt aorta. Incubation of vessels with Tyrphostin A-9 restored phosphorylation of Pyk2 and paxillin.


CONCLUSIONS
Increased activation of Pyk2 contributes to increased vascular contractile-responses in DOCA-salt mice.
Giachini
Fernanda R C
FR
Medical College of Georgia, Department of Physiology, Augusta, GA, USA, 30904.
Carneiro
Fernando S
FS
Lima
Victor V
VV
Carneiro
Zidonia N
ZN
Carvalho
Maria Helena C
MH
Fortes
Zuleica B
ZB
Webb
R Clinton
RC
Tostes
Rita C
RC