Optical properties, mitochondria, and sutures of lenses of fishes: a comparative study of nine species

Bantseev, Vladimir; Moran, K.L.; Dixon, D. George; Trevithick, John R.; Sivak, J. G.

doi:10.1139/z03-223

Cited by 19 publications

(9 citation statements)

References 26 publications

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“…Consequently, spherical lenses are found in most aquatic species (including teleosts, amphibians, reptiles, birds, and mammals; Walls,1942; Rochon‐Duvigneaud,1943; Duke‐Elder,1958). Nonetheless, aspherical lenses are present in a number of aquatic species, including the Australian lungfish (Bailes et al,2007), some species of lampreys (Collin and Fritzsch,1993; Collin et al,1999), other elasmobranchs (Rochon‐Duvigneaud,1943; Gilbert,1963; Lisney,2004), and some actinopterygian fishes (Munk,1984,1986; Pettigrew and Collin,1995; Douglas et al,2002; Bantseev et al,2004). The asphericity of the lens in C. punctatum is relatively small and reduces slightly with growth; the equatorial lens diameter is 12% larger than the axial lens diameter in embryos, dropping to 8% larger in adults.…”

Section: Discussionmentioning

confidence: 99%

Retinal neurogenesis and ontogenetic changes in the visual system of the brown banded bamboo shark, Chiloscyllium punctatum (hemiscyllidae, elasmobranchii)

Harahush

Hart

Green

et al. 2008

J of Comparative Neurology

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The development of the eye of the oviparous brown banded bamboo shark, Chiloscyllium punctatum, was monitored from egg deposition through adulthood. The order and timing of retinal cell differentiation were assessed by light and transmission electron microscopy. As in other vertebrates, the ganglion cells are the first to differentiate, in this case by 81 days post-egg deposition (dpd). The order then deviates from what is typically quoted for vertebrates, with the Müller and amacrine cells differentiating morphologically around the same time, followed by the bipolar cells (101 dpd) and finally the horizontal cells and photoreceptors (124 dpd). The neural retina is fully differentiated and synaptic connections are formed approximately 1 month prior to hatching, which occurs at about 158 dpd. The mature retina is duplex, with a peak rod to cone ratio of approximately 12:1. The eye and lens of C. punctatum continue to grow throughout life and become less aspherical with growth; the equatorial (nasotemporal) lens diameter is 12% larger than the axial (anterior-posterior) lens diameter in embryos and 8% larger in adults. Access to developmental stages and the protracted gestational period of C. punctatum make it a highly valuable model for developmental studies of the visual system. This study also provides an evolutionary perspective on retinal neurogenesis in an elasmobranch.

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Section: Discussionmentioning

confidence: 99%

Retinal neurogenesis and ontogenetic changes in the visual system of the brown banded bamboo shark, Chiloscyllium punctatum (hemiscyllidae, elasmobranchii)

Harahush

Hart

Green

et al. 2008

J of Comparative Neurology

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“…Lens diameter was analyzed using Adobe Photoshop 6.0. Teleost lenses are close to spherical in shape (1), and therefore changes in the diameter will be proportional to changes in lens volume. All lenses were cultured in control medium (300 mmol/ kg) for 1 wk before starting experiments, and only clear lenses were used.…”

Section: Methodsmentioning

confidence: 99%

N-acetylhistidine, a novel osmolyte in the lens of Atlantic salmon (Salmo salar L.)

Rhodes

Breck²,

Waagbø³

et al. 2010

American Journal of Physiology-Regulatory, Integrative and Comp

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-Volume homeostasis is essential for the preservation of lens transparency and this is of particular significance to anadromous fish species where migration from freshwater to seawater presents severe osmotic challenges. In Atlantic salmon (Salmo salar L.), aqueous humor (AH) osmolality is greater in fish acclimated to seawater compared with young freshwater fish, and levels of lens N-acetylhistidine (NAH) are much higher in seawater fish. Here we investigate NAH as an osmolyte in the lenses of salmon receiving diets either with or without histidine supplementation. In the histidine-supplemented diet (HD) histidine content was 14.2 g/kg, and in the control diet (CD) histidine content was 8.9 g/kg. A transient increase in AH osmolality of 20 mmol/kg was observed in fish transferred from freshwater to seawater. In a lens culture model, temporary decreases in volume and transparency were observed when lenses were exposed to hyperosmotic conditions. A positive linear relationship between extracellular osmolality and lens NAH content was also observed, whereas there was no change in lens histidine content. Hypoosmotic exposure stimulated [ 14 C]-histidine efflux by 9.2-and 2.6-fold in CD and HD lenses, respectively. NAH efflux, measured by HPLC, was stimulated by hypoosmotic exposure to a much greater extent in HD lenses. In vivo, lens NAH increased in response to elevated AH osmolality in HD but not CD fish. In conclusion, NAH has an important and novel role as a compatible osmolyte in salmon lens. Furthermore, it is the major osmolyte that balances increases in AH osmolality when fish move from freshwater to seawater. A deficiency in NAH would lead to a dysfunction of the normal osmoregulatory processes in the lens, and we propose that this would contribute to cataract formation in fish deficient in histidine. histidine PREVALENCE OF CATARACT IN farmed Atlantic salmon (Salmo salar L.) has increased in recent years (3) and this has been linked to the removal of a rich source of dietary histidine (blood meal) (7). Several recent studies have investigated the possible causes of cataract in farmed salmon (6, 9, 30), although the mechanisms involved remain to be elucidated.Osmotic stress has been shown to contribute to cataract formation in multiple species, including man (19). Efficient volume regulation is crucial for the maintenance of lens transparency and disruption to the tightly packed and highly ordered cells and proteins that make up the lens will cause a loss of lens transparency. In fish there are numerous examples where osmotic factors have been shown to play a role in cataract development (20), and the anadromous life cycle of the Atlantic salmon exposes the fish to particularly severe osmotic stress. The early part of salmon development is spent in freshwater as parr followed by transformation to smolts before entering the sea. Despite the physiological changes associated with parr-smolt transformation, a preadaption for life in seawater, reversible osmotic cataracts, are commonly described immediately aft...

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“…may become more important to provide environmental information (Gordon, 1954;Montgomery, 1989;Smith, 1989a). The importance of olfaction, touch, and taste in eels in general is well known (Bantseev et al, 2004) and has been documented in detail for Muraenidae (Santos and Castro, 2003), Anguillidae (Pankhurst and Lythgoe, 1983) and Ophichthidae (Bozzano, 2003). Observations on foraging behavior of P. boro confirm the importance of olfaction and touch, as the fish move actively along the bottom, regularly probing into the sediment with their snout (personal observation).…”

Section: Discussionmentioning

confidence: 82%

Pisodonophis boro (ophichthidae: anguilliformes): Specialization for head‐first and tail‐first burrowing?

Schepper

Kegel

Adriaens

2007

Journal of Morphology

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The rice paddy eel, Pisodonophis boro (P. boro), is of special interest because of its peculiar burrowing habits. P. boro penetrates the substrate tail-first, a technique common for ophichthids, but it is able to burrow head-first as well. P. boro exhibits three feeding modes: inertial feeding, grasping, and spinning. Rotational feeding is a highly specialized feeding mode, adopted by several elongate, aquatic vertebrates and it is likely that some morphological modifications are related to this feeding mode. The detailed morphology of the head and tail of P. boro is examined with the goal to apportion the anatomical specializations among head-first burrowing, tail-first burrowing, and rotational feeding. The reduced eyes, covered with thick corneas may be beneficial for protection during head-first burrowing, but at the same time decreased visual acuity may have an impact on other sensory systems (e.g. cephalic lateral line system). The elongated and pointed shape of the skull is beneficial for substrate penetration. The cranial bones and their joints, which are fortified, are advantageous for resisting high mechanical loads during head-first burrowing. The aponeurotic connection between epaxial and jaw muscles is considered beneficial for transferring these forces from the body to the head during rotational feeding. Hypertrophied jaw muscles facilitate a powerful bite, which is required to hold prey during spinning movements and variability in the fiber angles of subdivisions of jaw muscles may be beneficial for preventing the lower jaw from being dislodged or opened. Furthermore, firm upper (premaxillo-ethmovomerine complex) and lower jaws (with robust coronoid processes) and high neurocranial rigidity are advantageous for a solid grip to hold prey during rotational feeding. The pointed shape of the tail and the consolidated caudal skeleton are beneficial for their tail-first burrowing habits. It is quite likely that the reduction of the caudal musculature is related to the tail-first burrowing behavior because the subtle movements of the caudal fin rays are no longer required.

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Optical properties, mitochondria, and sutures of lenses of fishes: a comparative study of nine species

Cited by 19 publications

References 26 publications

Retinal neurogenesis and ontogenetic changes in the visual system of the brown banded bamboo shark, Chiloscyllium punctatum (hemiscyllidae, elasmobranchii)

Retinal neurogenesis and ontogenetic changes in the visual system of the brown banded bamboo shark, Chiloscyllium punctatum (hemiscyllidae, elasmobranchii)

N-acetylhistidine, a novel osmolyte in the lens of Atlantic salmon (Salmo salar L.)

Pisodonophis boro (ophichthidae: anguilliformes): Specialization for head‐first and tail‐first burrowing?

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