Effects of pertussis toxin on vasodilation and cyclic GMP in bovine mesenteric arteries and demonstration of a 40 kD soluble protein ribosylation substrate for pertussis toxin.
The inhibitory nucleotide-regulatory protein (Gl) has been shown to lose its adenylate cyclase inhibitory effect upon treatment with pertussis toxin. To find out whether a pertussis sensitive mechanism is involved in the regulation of the cGMP-system, bovine mesenteric arteries were incubated in buffer containing pertussis toxin, and the relaxation and intracellular cGMP accumulation induced by different groups of vasodilating agents were studied. The present results show a pertussis toxin induced decrease in relaxation as well as a decrease in the cGMP-elevation induced by the endothelium dependent vasodilators acetylcholine and calcium ionophore A 23187. Arteries treated with atrial natriuretic peptide showed no alterations in relaxation or cGMP content after incubation with pertussis toxin. A 40 kD soluble ribosylation substrate for pertussis toxin was identified in bovine mesenteric artery. These results suggest that a pertussis toxin sensitive mechanism is involved in the vasodilating mechanism of acetylcholine and calcium ionophore A 23187, while no evidence for such a mechanism could be found regarding the vasodilatory action of atrial natriuretic peptide.
Ljusegren
M E
ME
Department of Biology, Linköping University, Sweden.
Axelsson
K L
KL
Ahlner
J
J
Karlsson
J O
JO
Andersson
R G
RG
Magnusson
B R
BR
Friedman
R L
RL
D000109:Acetylcholine / Q000494:pharmacology; D000246:Adenosine Diphosphate Ribose / Q000378:metabolism; D037361:Adenylate Cyclase Toxin; D000818:Animals; D009320:Atrial Natriuretic Factor / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002417:Cattle; D046508:Culture Techniques; D006152:Cyclic GMP / Q000378:metabolism*; D008638:Mesenteric Arteries / Q000187:drug effects* / Q000502:physiology; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology; D037342:Pertussis Toxin; D014664:Vasodilation / Q000187:drug effects*; D010566:Virulence Factors, Bordetella / Q000494:pharmacology*
D037361:Adenylate Cyclase Toxin; D010566:Virulence Factors, Bordetella; D000246:Adenosine Diphosphate Ribose; D000001:Calcimycin; D009320:Atrial Natriuretic Factor; D037342:Pertussis Toxin; D006152:Cyclic GMP; D000109:Acetylcholine