Related Experiment Video
Updated: May 31, 2026
04:37
Reproductive Techniques for Ovarian Monitoring and Control in Amphibians
Published on: May 12, 2019
Developmental changes in interrenal responsiveness in anuran amphibians.
Karen A Glennemeier1, Robert J Denver
1Department of Biology, University of Michigan, Ann Arbor, Michigan 48109-1048.
Integrative and Comparative Biology
|June 29, 2011
Summary
Amphibian tadpoles show developed stress axis responsiveness early in development. Both species responded to stress and ACTH, with younger tadpoles exhibiting greater corticosterone production.
Area of Science:
- Comparative physiology
- Endocrinology
- Developmental biology
Background:
- The hypothalamo-pituitary-interrenal (HPI) axis regulates stress response in vertebrates.
- Developmental changes in HPI axis basal activity are known in amphibians, but responsiveness to stressors is less understood.
Purpose of the Study:
- To investigate developmental changes in the responsiveness of the amphibian HPI axis to stress and ACTH.
- To compare these developmental patterns between two anuran species: Rana pipiens and Xenopus laevis.
Main Methods:
- Measured whole-body corticosterone content as an indicator of HPI axis activity.
- Exposed tadpoles at different developmental stages to laboratory shaking/confinement stress and ACTH injection.
- Analyzed corticosterone levels in Rana pipiens and Xenopus laevis.
Main Results:
- Both species showed corticosterone responses to stress and ACTH, indicating developed interrenal responsiveness even in premetamorphic tadpoles.
- Responsiveness varied by developmental stage, with premetamorphic tadpoles exhibiting the greatest response.
- Species-specific patterns in basal corticosterone levels were observed across development.
Conclusions:
- Amphibian tadpoles possess a functional stress axis capable of responding to environmental challenges early in development.
- Comparative studies are crucial for understanding the evolution and development of stress axis regulation.
Related Concept Videos
01:24Renal Tubule and Collecting Duct
The renal tubule is divided into three parts: the proximal convoluted tubule (PCT), the Loop of Henle (LOH), and the distal convoluted tubule (DCT).
Proximal Convoluted Tubule (PCT):
The PCT is the initial segment of the renal tubule, extending from the Bowman's capsule that encloses the glomerulus. Its convoluted structure and microvilli-lined cells increase the surface area for reabsorption. The PCT reabsorbs glucose, amino acids, sodium, and water from the filtrate, ensuring essential...
Proximal Convoluted Tubule (PCT):
The PCT is the initial segment of the renal tubule, extending from the Bowman's capsule that encloses the glomerulus. Its convoluted structure and microvilli-lined cells increase the surface area for reabsorption. The PCT reabsorbs glucose, amino acids, sodium, and water from the filtrate, ensuring essential...
01:20Physiology of the Genitourinary System III: Urine Concentration and Dilution
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...
01:33Hormonal Regulation
The renin-aldosterone system is an endocrine system which guides the renal absorption of water and electrolytes, thus managing blood pressure and osmoregulation. Activation of the system begins in the kidneys with a small cluster of cells adjacent to the afferent and efferent blood vessels of the renal corpuscle. As the nephrons are filtering blood, juxtaglomerular cells monitor blood pressure. If they detect a decrease in pressure, they release the hormone renin into the bloodstream.
01:22Physiology of the Genitourinary System II: Tubular Reabsorption and Secretion
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...
01:20Formation of Dilute Urine
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...
01:29Renal Regulation of Acid-Base Balance
Metabolic reactions in the body produce nonvolatile acids, such as sulfuric acid, which generate an acid load of approximately 1 mEq of H+ per kilogram of body weight daily. Excreting H+ in the urine is essential to balance this acid load.
In the kidneys, cells within the proximal convoluted tubules (PCT) and the collecting ducts secrete hydrogen ions (H+) into the tubular fluid. Specifically, in the PCT, Na+/H+ antiporters secrete H+ while reabsorbing Na+.
However, the intercalated cells in...
In the kidneys, cells within the proximal convoluted tubules (PCT) and the collecting ducts secrete hydrogen ions (H+) into the tubular fluid. Specifically, in the PCT, Na+/H+ antiporters secrete H+ while reabsorbing Na+.
However, the intercalated cells in...