maximum velocity


max·i·mum ve·loc·i·ty (Vmax),

1. the maximum rate of an enzyme-catalyzed reaction that can be achieved by progressively increasing the substrate concentration at a given enzyme concentration; in cases of substrate inhibition, Vmax is an extrapolated value in the absence of such inhibition; Compare: Michaelis-Menten equation. 2. the maximum initial rate of shortening of a myocardial fiber that can be obtained under zero load; used to evaluate the contractility of the fiber.

max·i·mum ve·lo·ci·ty

(Vmax) (mak'si-mŭm vĕ-los'i-tē) 1. The maximum rate of an enzyme-catalyzed reaction that can be achieved by progressively increasing the substrate concentration at a given enzyme concentration; in cases of substrate inhibition. Vmax is an extrapolated value in the absence of such inhibition. 2. The maximum initial rate of shortening of a myocardial fiber that can be obtained under zero load; used to evaluate the contractility of the fiber.