Uptake of enalapril by rabbit small intestinal brush-border membrane vesicles

S Kitagawa1, J Takeda, S Sato

  • 1Niigata College of Pharmacy, Japan.

Related Concept Videos

Drug Elimination by Renal Route: Tubular Secretion01:15

Drug Elimination by Renal Route: Tubular Secretion

Once the process of glomerular filtration is completed, blood carrying unfiltered drug molecules traverses through efferent arterioles and makes its way into the peritubular capillaries in the proximal tubule. A variety of carriers play a pivotal role in actively secreting drugs from these peritubular capillaries into the tubular fluid. The organic anion transporter transfers acidic drugs, against an electrochemical gradient, from the peritubular capillaries into the renal tubule cells and...
Reabsorption and Secretion in the Loop of Henle01:17

Reabsorption and Secretion in the Loop of Henle

The thick ascending limb of the nephron loop has Na+–K+–2Cl− symporters in the apical membranes of its cells. These symporters simultaneously reclaim one sodium ion, one potassium ion, and two chloride ions from the tubular fluid. Sodium ions are actively transported into the interstitial fluid at the base and sides of the cell, diffusing into the vasa recta. Chloride ions move through leakage channels in the basolateral membrane into the interstitial fluid and then into the vasa recta.
Methods for Studying Drug Absorption: In vitro01:16

Methods for Studying Drug Absorption: In vitro

In vitro experiments are crucial for understanding the transport and absorption of drugs through biological materials. These studies employ varied methods such as the diffusion cell method, the everted sac technique, and the everted ring technique.
The diffusion cell method uses a two-compartment cell, including a donor compartment with the drug solution, which simulates the environment where the drug is applied, and a receptor compartment with a buffer solution, which simulates the environment...
Methods for Studying Drug Absorption: In situ01:09

Methods for Studying Drug Absorption: In situ

In situ experiments, such as the Doluisio method and Single-Pass Perfusion technique, provide critical insights into drug uptake by simulating in vivo conditions for drug absorption.
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,...
Renal Drug Excretion: Glomerular Filtration01:02

Renal Drug Excretion: Glomerular Filtration

The kidney serves as the primary organ responsible for eliminating drugs and their metabolites from the body. This process, known as renal elimination, starts with glomerular filtration and results in urine formation. Each kidney houses millions of functional units called nephrons, where urine production occurs. A nephron has two main components: a renal corpuscle and a renal tubule.
Drugs gain access to the kidney via the renal artery, which progressively branches off into afferent arterioles.
Renal Drug Excretion: Tubular Secretion01:28

Renal Drug Excretion: Tubular Secretion

Active tubular secretion is a robust, energy-demanding process that utilizes carrier systems to transport drugs into renal tubules. The active renal secretion systems include the organic anion transporter (OAT) for weak acids and the organic cation transporter (OCT) for weak bases. Structurally similar drugs can compete for the same transporter, potentially leading to drug accumulation and toxicity. However, this principle can be exploited therapeutically. One example is probenecid (Probalan),...