Effects of vitamin K3 on the hypotensive and bronchoconstrictor responses to bradykinin and histamine in the guinea pig.

Vitamin K3 significantly inhibits the bradykinin-induced bronchoconstriction in the guinea pig lungs in vivo. On the other hand, the bronchoconstrictor responses to histamine are significantly potentiated with vitamin K3. Vitamin K3 does not significantly alter the hypotensive responses to either brandykinin or histamine.