Histamine and bradykinin stimulate the phosphoinositide turnover in human umbilical vein endothelial cells via different G-proteins.
The G-proteins which regulate hormonal turnover of phosphoinositide (PI) in human umbilical vein endothelial cells have been investigated. A 40-41 kDa doublet present in the membranes of these cells was selectively ADP ribosylated by pertussis toxin (PTx), and this doublet was Gi alpha 2 and Gi alpha 3 according to immunoblotting with specific antisera. By contrast, a doublet of 24-26 kDa proteins in the same membrane preparations was ADP ribosylated by the C3 component of botulinum toxin (BoTx). PTx-dependent ADP ribosylation blocked stimulation of PI turnover by histamine, but did not affect stimulation by bradykinin, whereas BoTx (C2 + C3 components) had the opposite effect. Thus two different groups of G-proteins may be involved in hormone-dependent stimulation of PI turnover in human umbilical vein endothelial cells.
Voyno-Yasenetskaya
T A
TA
Institute of Experimental Cardiology, Moscow, USSR.
Panchenko
M P
MP
Nupenko
E V
EV
Rybin
V O
VO
Tkachuk
V A
VA
D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D001905:Botulinum Toxins / Q000494:pharmacology; D001920:Bradykinin / Q000494:pharmacology*; D004730:Endothelium, Vascular / Q000378:metabolism*; D019204:GTP-Binding Proteins / Q000378:metabolism*; D006150:Guanine Nucleotides / Q000494:pharmacology; D006632:Histamine / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D037342:Pertussis Toxin; D010716:Phosphatidylinositols / Q000378:metabolism*; D010566:Virulence Factors, Bordetella / Q000494:pharmacology
D006150:Guanine Nucleotides; D010716:Phosphatidylinositols; D010566:Virulence Factors, Bordetella; D000246:Adenosine Diphosphate Ribose; D006632:Histamine; D037342:Pertussis Toxin; D001905:Botulinum Toxins; D019204:GTP-Binding Proteins; D001920:Bradykinin