Effects of the aminopeptidase P inhibitor apstatin on bradykinin-induced inositol 1,4,5-triphosphate in neonatal rat cardiomyocytes.
We investigated the effect of apstatin (an aminopeptidase P inhibitor) on bradykinin-induced inositol 1,4,5-triphosphate (IP3) formation and glucose uptake in isolated neonatal rat cardiomyocytes. Apstatin enhanced bradykinin-induced IP3 formation in a dose-dependent manner. We found that 1 microM Hoe 140 (a bradykinin B2-receptor antagonist) significantly decreased the potentiation of bradykinin-induced IP3 production by 5 microM apstatin from 781.8+/-67.2 to 127.4+/-33.0 pmol/mg protein; 5 microM apstatin increased bradykinin-induced glucose uptake from 197.0+/-25.5 to 297.3+/-64.0 pmol/h per milligram of protein. The stimulation of glucose uptake with apstatin was blocked to 132.5+/-26.2 pmol/h per milligram of protein by 1 microM Hoe 140. We conclude that apstatin stimulates bradykinin-induced IP3 formation and glucose uptake by preventing the degradation of bradykinin.
Kudoh
A
A
Department of Anesthesiology, Hirosaki National Hospital, Japan.
Kudoh
E
E
Katagai
H
H
Takazawa
T
T
D000626:Aminopeptidases / Q000037:antagonists & inhibitors*; D000818:Animals; D000831:Animals, Newborn; D001920:Bradykinin / Q000494:pharmacology*; D002478:Cells, Cultured; D004305:Dose-Response Relationship, Drug; D005947:Glucose / Q000378:metabolism; D015544:Inositol 1,4,5-Trisphosphate / Q000096:biosynthesis* / Q000378:metabolism; D009206:Myocardium / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D010455:Peptides / Q000494:pharmacology*; D011480:Protease Inhibitors / Q000494:pharmacology*; D051381:Rats
D010455:Peptides; D011480:Protease Inhibitors; D015544:Inositol 1,4,5-Trisphosphate; D000626:Aminopeptidases; C022750:X-Pro aminopeptidase; D005947:Glucose; C097277:apstatin; D001920:Bradykinin