The renal excretion of 4'-carboxyphenylmethane sulfonanilide (caronamide)

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),...

As primary excretory organs, the kidneys maintain homeostasis by removing waste substances from the bloodstream. They comprise over a million units called nephrons, which serve as the kidney's functional units.
A nephron consists of two primary structures: the renal corpuscle and the renal tubule. The renal corpuscle contains the glomerulus, a network of capillaries where the first step of renal excretion, glomerular filtration, occurs. Blood pressure forces water, ions, and small molecules out...

During the process of renal excretion, as the glomerular filtrate progresses to the distal convoluted tubule (DCT), drugs that are highly permeable, lipophilic, and nonionized undergo passive reabsorption from the tubular fluid into the surrounding peritubular capillaries. This reabsorption process restricts their elimination through the kidneys. However, the majority of drugs are either weak acids or weak bases, and their ionization level is dependent on pH. By altering the pH of urine, the...

Tubular reabsorption, a process occurring post-glomerular filtration of drugs in the renal tubule, is a critical determinant of drug half-life. During the process of renal excretion, as the glomerular filtrate progresses to the distal convoluted tubule (DCT), drugs that are highly permeable, lipophilic, and nonionized undergo passive reabsorption from the tubular fluid into the surrounding peritubular capillaries. This reabsorption process restricts their elimination through the kidneys. This...

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...

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.