Related Experiment Video
Updated: Apr 24, 2026
09:31
Hemodynamic Precision in the Neonatal Intensive Care Unit using Targeted Neonatal Echocardiography
Published on: January 27, 2023
2.0K
Decreased serum osmolality promotes ductus arteriosus constriction
Rika Aoki1, Utako Yokoyama2, Yasuhiro Ichikawa1
1Cardiovascular Research Institute, Yokohama City University, 3-9 Fukuura, Kanazawa-ku, Yokohama, Kanagawa 236-0004, Japan Department of Pediatrics, Yokohama City University, Yokohama, Japan.
Cardiovascular Research
|September 6, 2014
Summary
Transient hypoosmolality after birth promotes ductus arteriosus (DA) closure in neonates. Maintaining proper serum osmolality may prevent patent DA (PDA) in extremely preterm infants.
Area of Science:
- Neonatal physiology
- Cardiovascular adaptation
- Perinatal medicine
Background:
- Dynamic physiological changes, including ductus arteriosus (DA) closure, occur at birth.
- Previous studies noted a transient decrease in serum osmolality in term neonates post-birth.
- The role of this transient hypoosmolality in DA closure remained uninvestigated.
Purpose of the Study:
- To investigate the role of postnatal serum osmolality changes in the closure of the ductus arteriosus.
- To understand the mechanisms underlying osmolality-induced DA constriction.
Main Methods:
- Studied serum osmolality changes and DA function in a rat model post-birth.
- Utilized hypotonic and hypertonic fluid challenges in rat DA rings and smooth muscle cells.
- Investigated the expression and function of the TRPM3 channel in rat DA.
- Correlated neonatal serum osmolality with DA patency in human preterm infants.
Main Results:
- Rats showed transient hypoosmolality post-birth, inducing DA ring constriction via TRPM3 activation.
- TRPM3 channel is crucial for the hypoosmolality-induced calcium transient in DA smooth muscle cells.
- Hypertonic fluid impaired DA closure in rats.
- Extremely preterm infants (<28 weeks) lacked hypoosmolality, exhibiting increased osmolality, particularly those with patent DA.
Conclusions:
- Transient postnatal hypoosmolality appears to facilitate ductus arteriosus closure.
- Therapeutic adjustments in serum osmolality may prevent patent DA in extremely preterm infants.
- Optimizing osmolality could improve treatment outcomes for extremely preterm neonates.
Related Concept Videos
01:25Regulation of Water Intake
2.2K
Osmolality refers to the number of solute particles per kilogram of solvent in a solution. Plasma osmolality specifically indicates the total number of solute particles per kilogram of water in blood plasma. This value reflects the body's hydration status and is tightly regulated through mechanisms controlling water intake and output. While water consumption is a conscious decision, the body has intrinsic regulatory systems to maintain fluid balance. Dehydration, a state of water deficit...
2.2K
01:22Diabetes Insipidus II: Pathophysiology
20
Normally, water balance is maintained through three interconnected mechanisms: the hypothalamic thirst center, the synthesis and release of antidiuretic hormone (ADH, or vasopressin), and the kidneys' responsiveness to this hormone. ADH is synthesized in the hypothalamus, released from the posterior pituitary, and acts on the distal nephron, allowing water reabsorption and concentrated urine production.Diabetes Insipidus and Its TypesIn diabetes insipidus (DI), this regulatory system is...
20
01:20Formation of Dilute Urine
3.5K
The formation of dilute urine is a critical renal adaptation that maintains fluid balance, particularly during periods of high fluid intake. This process primarily involves the juxtamedullary nephrons. By adjusting the permeability of water and ions in response to physiological conditions, the kidneys can either conserve or excrete water, resulting in concentrated or dilute urine.
Filtrate Osmolarity in the PCT
Initially, as the filtrate passes through the proximal convoluted tubule (PCT), its...
Filtrate Osmolarity in the PCT
Initially, as the filtrate passes through the proximal convoluted tubule (PCT), its...
3.5K
01:20Physiology of the Genitourinary System III: Urine Concentration and Dilution
1.3K
The kidneys concentrate or dilute urine to maintain water and electrolyte balance. Nephrons, particularly the loop of Henle, play a crucial role in this process through the countercurrent multiplication system. This system establishes a high osmolarity in the renal medulla, which is essential for water reabsorption. In the loop of Henle’s descending limb, water is reabsorbed into the surrounding medulla due to its permeability to water. In contrast, the ascending limb actively transports...
1.3K
01:23Formation of Concentrated Urine
4.1K
There is a gradient of solutes in the interstitial fluid from the renal cortex through the medulla, known as the medullary osmotic gradient. The juxtamedullary nephrons establish and maintain this gradient using countercurrent mechanisms with loops extending deep into the medulla. These nephrons also use countercurrent mechanisms to regulate urine volume and concentration. The interaction between the descending and ascending limbs of the nephron loop creates an osmotic gradient through...
4.1K
01:22Physiology of the Genitourinary System II: Tubular Reabsorption and Secretion
2.3K
The kidneys maintain homeostasis through filtration, reabsorption, and secretion. Tubular reabsorption and secretion are crucial in forming urine and regulating electrolytes, water balance, and waste elimination.Tubular Reabsorption and Secretion ProcessesTubular reabsorption is the process that reclaims essential substances such as electrolytes, glucose, amino acids, and water from the glomerular filtrate back into the bloodstream. This is achieved through passive and active transport...
2.3K