Rectal Reabsorption

Source: Joseph Donroe, MD, Internal Medicine and Pediatrics, Yale School of Medicine, New Haven, CT While its usefulness in cancer screening is debated, the male rectal examination remains an important part of the physical exam. The exam is indicated in selected patients with lower urinary tract symptoms, urinary and/or fecal incontinence or retention, back pain, anorectal symptoms, abdominal complaints, trauma patients, unexplained anemia, weight loss, or bone pain. There are no absolute...

Tubular secretion and reabsorption are two critical processes in the nephron tubule of the kidneys. When the fluid filtered from the glomerulus enters the proximal convoluted tubule, it is referred to as filtrate, and its composition changes due to tubular reabsorption and secretion. Tubular reabsorption is a selective process that starts when the filtrate enters the proximal tubules. It involves substances traveling through the transcellular route (through the tubule cell and peritubular...

The Proximal Convoluted Tubule, or PCT, plays a pivotal role in the body's filtration system. They are primarily responsible for reabsorbing solutes and water from the filtered fluid produced by the glomeruli. Most of the filtered water, ions, and organic solutes such as glucose and amino acids are reabsorbed by the PCT. Transport mechanisms involving sodium ions (Na+) contribute significantly to solute reabsorption. These mechanisms include symport and antiport processes. A key example is the...

Rectal temperature measurement is considered the most precise method for assessing core body temperature and typically registers higher than oral temperature. For adults, the rectal thermometer should be inserted 1 to 1.5 inches into the rectum to obtain the most accurate reading. Follow these steps for rectal temperature assessment: Step 1: Perform hand hygiene and don clean gloves to prevent cross-infection. Step 2: Position the patient in a side-lying position to better visualize the rectal...

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.