The effect of rate of perfusion, volume, pH of the perfusate, and partition coefficient of the drug on the rate of in situ nasal absorption in @entity35 was examined. The studies showed that the rate constant for the nasal absorption of @entity109 was independent of the rate of perfusion above a value of 2 mL/min. The nasal absorption of @entity13266 was found to depend on the pH of the perfusate with the @entity10555 anion being absorbed at a rate one-fourth of that of @entity13266 . The effect of lipid solubility on the extent of nasal absorption was studied using a series of barbiturates. The rate and extent of absorption was found to be dependent on the @entity3636 -water partition coefficient of the barbiturate. The effect of the volume of the perfusate on the absorption rate constant of @entity109 , @entity3971 red, @entity669 , and @entity1169 was studied. The data obtained showed that a linear relationship existed between the rate constants of absorption and the reciprocal of the volume of the perfusate. Using this in situ relationship it was possible to predict in vivo absorption rate constants for @entity1169 and @entity9109 when volumes of 0.1 mL were administered. The calculated values for these compounds were found to be close to those determined in in vivo experiments. This indicates that the in situ technique can be used to predict in vivo absorption rate constants.

Mechanism of nasal absorption of drugs I: Physicochemical parameters influencing the rate of in situ nasal absorption of drugs in XXXX .

@entity1169 :: ('MESH:D011433', 'Chemical') :: ['propranolol'] @entity13266 :: ('MESH:D019817', 'Chemical') :: ['benzoic acid'] @entity3636 :: ('MESH:D002725', 'Chemical') :: ['chloroform'] @entity3971 :: ('MESH:D019800', 'Chemical') :: ['phenol'] @entity9109 :: ('CHEBI:17895', 'Chemical') :: ['L-tyrosine'] @entity109 :: ('MESH:D010634', 'Chemical') :: ['phenobarbital'] @entity35 :: ('10116', 'Species') :: ['rats'] @entity669 :: ('CHEBI:18186', 'Chemical') :: ['tyrosine'] @entity10555 :: ('MESH:D001565', 'Chemical') :: ['benzoate']
@entity35 :: (10116,Species) :: ['rats']
