Related Experiment Video
Updated: Aug 7, 2026
08:00
Observation of the Ciliary Movement of Choroid Plexus Epithelial Cells Ex Vivo
Published on: July 13, 2015
Link between the ciliary process and lens equatorial current
S P Walsh1, J Sullivan, J W Patterson
1Department of Physiology, University of Connecticut Health Center, Farmington 06032.
Lens and Eye Toxicity Research
|January 1, 1992
Summary
Seasonal changes significantly impact frog lens equatorial currents, with norepinephrine application affecting these currents. The ciliary process epithelium plays a role in regulating these physiological changes.
Area of Science:
- Ophthalmology
- Physiology
- Neuroendocrinology
Background:
- Intraocular pressure (IOP) exhibits circadian and seasonal variations.
- These changes are influenced by the nervous system and norepinephrine release in the eye.
- The equatorial current of the lens is a key electrophysiological parameter in ocular physiology.
Purpose of the Study:
- To investigate the relationship between seasonal changes and the frog lens equatorial current.
- To determine the effect of topical norepinephrine application on the lens equatorial current.
- To explore the role of the ciliary process epithelium in modulating lens equatorial current.
Main Methods:
- Utilized a vibrating probe and microelectrodes to measure the K+ electrical loop and equatorial current (J) in frog lenses (Rana pipiens).
- Analyzed electrophysiological parameters of 270 normal frog lenses throughout the year.
- Assessed the impact of direct and topical norepinephrine application on lens equatorial current (J) and resistance (RJ).
Main Results:
- Observed threefold seasonal variations in equatorial current (J) amplitude and resistance (RJ).
- Equatorial current (J) was highest in winter, while resistance (RJ) peaked in late spring.
- Topical norepinephrine application increased the lens equatorial current, whereas direct application had no effect.
Conclusions:
- The magnitude of the frog lens equatorial current exhibits significant seasonal fluctuations.
- Norepinephrine, applied topically, modulates the lens equatorial current.
- The ciliary process epithelium is implicated in mediating the regulation of the lens equatorial current.
Related Concept Videos
01:22Microtubules in Signaling
The primary cilium, made up of microtubules, acts as antennae on the cell surfaces for relaying external stimuli into the cells. These fine hair-like structures are present, generally one per cell. These are non-motile cilia in a 9+0 microtubules arrangement, where the central pair of microtubules are absent. The primary cilia arise from the basal body embedded in the cell membrane. Intraflagellar transport (IFT) carries requisite proteins from the cytoplasm to the cilium because the primary...
01:05Mechanism of Ciliary Motion
The ciliary structures were first seen in 1647 by Antonie Leeuwenhoek while observing the protozoans. In lower organisms, these appendages are responsible for cell movement, while in higher organisms, these appendages help in the movement of the extracellular fluids within the body cavities.
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
01:05Mechanism of Ciliary Motion
The ciliary structures were first seen in 1647 by Antonie Leeuwenhoek while observing the protozoans. In lower organisms, these appendages are responsible for cell movement, while in higher organisms, these appendages help in the movement of the extracellular fluids within the body cavities.
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
The cilia are made up of microtubules in a 9+2 arrangement, with nine microtubule doublet ring bundles, surrounding a pair of central singlet microtubule bundles. The doublet microtubule bundles are...
01:20Muscles of the Eye
The muscles of the eye are sophisticated structures that control eye movement and focus, allowing for the precise and rapid adjustments necessary for vision. The human eye is controlled by ten muscles — six extraocular muscles, three intraocular muscles, and one primary eyelid retractor muscle.
Extraocular Muscles
The six extraocular muscles surround the eyeball and control its movements. They are responsible for a wide range of eye motions, including looking up, down, left, right, and rotating...
Extraocular Muscles
The six extraocular muscles surround the eyeball and control its movements. They are responsible for a wide range of eye motions, including looking up, down, left, right, and rotating...
01:17Accessory Structures of the Eye
Optical perception, or vision, is an extraordinary sense dependent on converting light signals received via the ocular organs. These organs, known as eyes, are securely positioned within the bony cavities of the skull, called orbits. The orbits serve a dual purpose: a protective shield for the ocular globes and a stable attachment point for the soft ocular tissues. The eye's external protective mechanisms include the eyelids, which are edged with lashes that act as a barrier against foreign...
01:16Focusing of Light in the Eye
Light rays enter the eye through the cornea, a transparent dome-shaped tissue that is the eye's outermost layer. The cornea bends or refracts, light rays traveling to the pupil. The shape of the cornea determines how much of the light is bent and whether the image will be focused correctly on the retina at the back of the eye. Once the light has passed through both refraction layers, it converges into a single focal point onto a small area. This is where photoreceptors start transforming...