Versuche zur biologischen Bedeutung der Lorenzinischen Ampullen bei den Elasmobranchiern

Dijkgraaf, S.; Kalmijn, Ad. J.

doi:10.1007/bf00298095

Cited by 55 publications

(19 citation statements)

References 14 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Important physiological properties of the ampulla of Lorenzini that are likely to be mediated by B K channels include sensitivity and accommodation [4,12,14, 31]. Receptor cells in the ampulla are tonically active and remarkably sensitive and can detect changes of less than 1 μV [11, 12, 14].…”

Section: 1 Discussionmentioning

confidence: 99%

“…Receptor cells in the ampulla are tonically active and remarkably sensitive and can detect changes of less than 1 μV [11, 12, 14]. Spontaneous activity of the receptor cells in vivo produces 20 Hz oscillations in epithelial current that result from interaction between calcium channels in the apical face and voltage dependent K + channels in the basal face [11,12].…”

Section: 1 Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Calcium activated K+ channels in the electroreceptor of the skate confirmed by cloning. Details of subunits and splicing

King

Ling

Kao

et al. 2016

Gene

View full text Add to dashboard Cite

Elasmobranchs detect small potentials using excitable cells of the ampulla of Lorenzini which have calcium-activated K+ channels, first described in l974. A distinctive feature of the outward current in voltage clamped ampullae is its apparent insensitivity to voltage. The sequence of a BK channel α isoform expressed in the ampulla of the skate was characterized. A signal peptide is present at the beginning of the gene. When compared to human isoform 1 (the canonical sequence), the largest difference was absence of a 59 amino acid region from the S8-S9 intracellular linker that contains the strex regulatory domain. The ampulla isoform was also compared with the isoform predicted˜ in late skate embryos where strex was also absent. The BK voltage sensors were conserved in both skate isoforms. Differences between the skate and human BK channel included alternative splicing. Alternative splicing occurs at seven previously defined sites that are characteristic for BK channels in general and hair cells in particular. Skate BK sequences were highly similar to the Australian ghost shark and several other vertebrate species. Based on alignment of known BK sequences with the skate genome and transcriptome, there are at least two isoforms of Kcnma1α expressed in the skate. One of the β subunits (β4), which is known to decrease voltage sensitivity, was also identified in the skate genome and transcriptome and in the ampulla. These studies advance our knowledge of BK channels and suggest further studies in the ampulla and other excitable tissues.

show abstract

Section: 1 Discussionmentioning

confidence: 99%

Section: 1 Discussionmentioning

confidence: 99%

Calcium activated K+ channels in the electroreceptor of the skate confirmed by cloning. Details of subunits and splicing

King

Ling

Kao

et al. 2016

Gene

View full text Add to dashboard Cite

show abstract

“…Later, his PhD-student A.J. Kalmijn succeeded in keeping dogfi sh at Utrecht in circular pools, where the dogfi sh could not hurt their rostra by bumping against the walls of the earlier used rectangular glass tanks (Dijkgraaf and Kalmijn, 1966). Another problem was that conditioning dogfi sh in behavioural experiments was rather diffi cult, if not impossible (Pals, 1982a;Pals, 1982b;Peters et al, 2007b).…”

Section: Th E Aegis Of Academic Freedommentioning

confidence: 99%

“…It had been easier to study spontaneous behaviour (Dijkgraaf and Kalmijn, 1962;Kalmijn, 1971). Implanting electrodes in order to record activity of the nerves innervating the ampullae of Lorenzini was also a challenge (Dijkgraaf and Kalmijn, 1966). I had the privilege to join Kalmijn's research group in 1963, and was invited to record from those nerves in unrestrained dogfi sh in order to asses the spectrum of stimuli to which they might respond.…”

Section: Th E Aegis Of Academic Freedommentioning

confidence: 99%

“…Unfortunately this was not the case, which gave us the impression at that time to have failed to implant the electrodes properly. Luckily, by returning to the lab for an evening lecture and checking the animal and the implanted electrodes once more after an apparent unsuccessful implantation eff ort, I got hold of the electrophysiological recordings published in Dijkgraaf and Kalmijn (1966). Eventually Kalmijn demonstrated in a spontaneous behaviour experiment, how the electric sense of dogfi sh was used in the detection and location of prey (Kalmijn, 1971).…”

Section: Th E Aegis Of Academic Freedommentioning

confidence: 99%

See 1 more Smart Citation

Academic freedom and the discovery of electroreception in catfish and dogfish

Peters¹

2008

Animal Biol

View full text Add to dashboard Cite

A brief sketch is given of the changing interpretation of Academic Freedom at the universities in Th e Netherlands during the last half of the twentieth century, by discussing the discoveries of electroreception in catfi sh, Ameiurus nebulosus , and dogfi sh, Scyliorhinus canicula . It is concluded that science is no longer hypothesis-driven, but money-driven. Whereas innovation and discoveries belong typically to the domain of the individual scientist and fl ourish in a bottom-up organisation, the funding agencies of today advocate a top-down approach to stimulate creativity. Apparently the resultant institutionalization has not the desired result. Could electroreception research be initiated in 2008?Th e scene is a University in the Netherlands. Th e year is 2008. Th e discipline is biology. A student 1 wants to learn more about a particular type of behaviour he has noticed when he was visiting a marine aquarium during a stay abroad. Th is particular type of behaviour was that a dogfi sh, Scyliorhinus canicula, turned away its head when the animal keeper tried to feed it by putting a piece of squid on a rusty piece of iron wire in the vicinity of its head. Th e remarkable thing was that turning away its head did not occur when the piece of squid was off ered on a glass rod. Th e student went to see the 1) Persons of either gender will be referred to as "he". Preface

show abstract

Structural Characteristics and Development of Ampullary Organs in Acipenser naccarii

Camacho¹,

Ostos²,

Llorente³

et al. 2007

The Anatomical Record

View full text Add to dashboard Cite

Ampullary organs of Acipenser naccarii sturgeons were examined by optical and electronic microscopy (transmission electron microscopy and scanning electron microscopy) from hatching until 1 month later when the juvenile phase is completely established. It was observed that, when A. naccarii begins to feed actively, the ultrastructural characteristics of ampullary organs already correspond to those of adult animals. These organs may, therefore, be functional and, together with taste buds, facilitate food search after exhaustion of yolk sac food reserves. Mature ampullary organs of A. naccarii are formed by an ampulla that communicates with the exterior by means of a short channel. These ampullae correspond to the sensory portion of these receptors and are formed by two cell types: receptor cells and support cells. Receptor cells present a kinocilium on their free surface and establish ribbon synapses with axon nerve endings that arise from the underlying conjunctive tissue. Support cells enclose receptor cells, bear stereocilia and occasional cilia, and are of a secretory nature. The mucus associated with ampullary organs mainly comprises neutral mucopolysaccharides, whereas mucopolysaccharides are usually acid in other fish groups.

show abstract

Versuche zur biologischen Bedeutung der Lorenzinischen Ampullen bei den Elasmobranchiern

Cited by 55 publications

References 14 publications

Calcium activated K+ channels in the electroreceptor of the skate confirmed by cloning. Details of subunits and splicing

Calcium activated K+ channels in the electroreceptor of the skate confirmed by cloning. Details of subunits and splicing

Academic freedom and the discovery of electroreception in catfish and dogfish

Structural Characteristics and Development of Ampullary Organs in Acipenser naccarii

Contact Info

Product

Resources

About