Related Experiment Video
Updated: Feb 3, 2026
08:01
The Diffusion of Passive Tracers in Laminar Shear Flow
Published on: May 1, 2018
9.0K
Reconsidering the Passive Diffusion Model of Steroid Hormone Cellular Entry
Sarah D Neuman1, Arash Bashirullah1
1Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin-Madison, Madison, WI 53705, USA.
Developmental Cell
|November 7, 2018
Summary
Steroid hormones were believed to enter cells passively. However, new research shows that steroid hormone transport into Drosophila cells requires specific protein transporters for entry.
Area of Science:
- Cell Biology
- Molecular Biology
- Developmental Biology
Background:
- Steroid hormones are crucial signaling molecules regulating diverse physiological processes.
- Cellular uptake of steroid hormones was traditionally attributed to passive diffusion across the plasma membrane.
Purpose of the Study:
- To investigate the mechanism of steroid hormone entry into target cells.
- To determine if protein transporters are involved in steroid hormone cellular uptake.
Main Methods:
- Utilized Drosophila melanogaster as a model organism.
- Employed genetic and molecular techniques to study steroid hormone transport.
Main Results:
- Demonstrated that steroid hormones require specific protein transporters for cellular entry in Drosophila.
- Challenged the long-held model of passive diffusion for steroid hormone uptake.
Conclusions:
- The cellular entry of steroid hormones is an active, protein-mediated process in Drosophila.
- Identified a novel mechanism for steroid hormone transport, impacting our understanding of endocrine signaling.
Related Concept Videos
02:13Types of Hormones
83.6K
Hormones can be classified into three main types based on their chemical structures: steroids, peptides, and amines. Their actions are mediated by the specific receptors they bind to on target cells.
83.6K
01:17Passive Diffusion: Overview and Kinetics
1.4K
Passive diffusion is a critical process that allows small lipophilic drugs to cross the cell membrane along a concentration gradient. This mechanism's efficiency depends on four primary factors: the membrane's surface area, the drug's lipid-water partition coefficient, the concentration gradient, and the membrane's thickness.
When administered orally, drugs establish a substantial concentration gradient between the gastrointestinal (GI) lumen and the bloodstream, expediting...
When administered orally, drugs establish a substantial concentration gradient between the gastrointestinal (GI) lumen and the bloodstream, expediting...
1.4K
01:12Diffusion
218.6K
Diffusion is the passive movement of substances down their concentration gradients—requiring no expenditure of cellular energy. Substances, such as molecules or ions, diffuse from an area of high concentration to an area of low concentration in the cytosol or across membranes. Eventually, the concentration will even out, with the substance moving randomly but causing no net change in concentration. Such a state is called dynamic equilibrium, which is essential for maintaining overall...
218.6K
01:21Diffusion
6.4K
Diffusion is a type of passive transport. In passive transport, a substance tends to move from an area of high concentration to an area of low concentration until the concentration is equal across the space. For example, take the diffusion of substances through the air. When someone opens a perfume bottle in a room filled with people, the perfume is at its highest concentration in the bottle and is at its lowest at the edges of the room. The perfume vapor will diffuse, or spread away, from the...
6.4K
01:33Hormonal Regulation
36.1K
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.
36.1K
01:40Hormonal Regulation
48.1K
Hormones regulate a significant portion of digestion through activation of the neuroendocrine system. The neuroendocrine system of digestion contains many different hormones all with multiple functions that are both, directly and indirectly, involved in digestion.
48.1K