Related Experiment Video
Updated: Aug 11, 2026

Real-time X-ray Imaging of Lung Fluid Volumes in Neonatal Mouse Lung
Published on: July 18, 2016
Pulmonary absorption of drugs in the neonatal rat
Abstract:
To compare the pulmonary absorption of drugs in newborn rats (3-27 days old) with that in adults, 0.01-0.1 ml of Krebs-Ringer phosphate solution (pH 7.4) containing a drug was administered to anesthetized animals by way of a catheter introduced through a tight-fitting tracheal cannula. After various times, lungs and trachea were removed and assayed for drug that remained. Semilogarithmic plots of percent drug remaining against time yielded a straight line for each compound. The lipid-soluble drugs procaine amide and sulfisoxazole were absorbed at similar rates in newborn and adult rats. In contrast, the lipid-insoluble drugs tetraethylammonium, p-aminohippuric acid, and mannitol were absorbed approximately 2 times more rapidly in younger rats (3-12 days) than in older animals (18 day, 27 day, or adult). The results suggested that the respiratory tract membranes of 3- to 12-day-old rats have a greater porosity than those of older animals.
Related Concept Videos
Methods for Studying Drug Absorption: In situ
The Doluisio method involves perfusing a prepared segment of a rat's small intestine with a solution of radiolabeled drug and a non-absorbable marker. This helps to differentiate between absorbed and non-absorbed drug concentrations. The intestinal segment is connected at both ends using tubing and syringes,...
Non-Oral Extravascular Drug Absorption Routes
Lipophilic drugs that are stable at salivary pH (6) and exhibit minimal binding to the oral mucosa are absorbed more effectively...
Drug Excretion: Pulmonary and Glandular Routes
Drugs can also be excreted in breast milk, which is crucial for breastfeeding infants. The process...
Pharmacokinetics in Pediatric Patients: Overview and Drug Absorption
Pharmacokinetics in Pediatric Patients: Drug Distribution
Pharmacokinetics in Pediatric Patients: Drug Excretion

