Acetylcholinesterase decrease in the optic lobe after unilateral eye deprivation

Unilateral eye enucleation in a teleost and a turtle results in progressive AChE decrease in the optic lobe controlateral to the extirpated eye. The final difference reaches 15% in teleost and more than 20% in turtle. No drastic differences in localization, but a rearrangement of histochemical pattern, due to the degeneration of retinal fibres, is noticed.     

Circulating serotonin in vertebrates

The role of circulating serotonin is unclear and whether or not serotonin is present in the blood of non-mammalian species is not known. This study provides the first evidence for the presence of serotonin in thrombocytes of birds and three reptilian species, the endothermic leatherback sea turtle, the green sea turtle and the partially endothermic American alligator. Thrombocytes from a fresh water turtle, American bullfrog, Yellowfin tuna, and Chinook salmon did not contain serotonin. Serotonin is a vasoactive substance that regulates skin blood flow, a major mechanism for endothermic body temperature regulation, which could explain why circulating serotonin is present in warm-blooded species. The temperature sensitivity of human blood platelets with concomitant changes in serotonin content further supports a link between circulating serotonin and thermoregulation. Phylogenetic comparison of the presence of circulating serotonin indicated an evolutionary divergence within reptilian species that might coincide with the emergence of endothermy.Received 2 April 2005; received after revision 15 May 2005; accepted 15 June 2005     

The evolution of a trading zone: a case study of the turtle excluder device

This paper explores the evolution of a trading zone by organizing the case study of turtle excluder devices within the model proposed by Collins et al. (2007). The case study offers evidence that trading zones do evolve and that the concepts of enforced and fractionated trading zones hold practical utility for describing and defining the complexities of actual exchanges. In this case a trading zone evolved from enforced to fractionated and ultimately diverged into two trading zones. For each step of the evolution I describe the forces that drove these transitions. Finally, I present an adapted trading zone model that is conceptually a better fit for the turtle excluder device case study.     

Biotin-binding proteins in eggs of oviparous vertebrates

Summary Biotin-binding was found in the egg whites and yolks of all 23 avian species studied, and in a turtle, but the amount varied considerably even in related species. There was no clear correlation in biotin-binding between egg white and yolk in various species. Antigenic determinants of avidin in different species have changed in the course of evolution as compared with those of chicken egg white avidin.We thank Mr Jukka Peltonen and Mr Antti Karlin for the collection of the avian eggs with permission obtained from the Ministry of Agriculture, and Mr Reino Saarinen for the turtle eggs. The authors are indebted to Mrs Outi Kurronen Miss Riitta Mero and Miss Tiina-Maija Mattila for technical assistance. This work was supported by the Ford Foundation Grants No. 760-0526 and No. 790-0665.     

Changes induced by manganese in fish testis

Summary Exposure ofColisa fasciatus, a freshwater teleost, to 2500 mg/l manganese sulphate for 90 h caused decreased spermatogenic activity and hemorrhage in the testes.     

C-reactive protein-like precipitins in lumpsucker (Cyclopterus lumpus L.) gametes

Summary A precipitin to pneumococcal and fungal C-substance, found in both ova and spermatozoa from a marine teleost fish, has similarities to mammalian C-reactive protein (CRP). This is the first demonstration of a CRP-like protein in the gametes of any species and adds further interest to the as yet unknown physiological role of CRP in vertebrates.     

Influence of oxygen concentration on development ofDrosophila melanogaster

Summary 1st, 2nd, and early 3rd instarDrosophila larvae are extremely sensitive to 100% O₂ or 75% O₂/25% N₂ (at atmospheric pressure) whereas eggs, late 3rd instar larvae, and pupae are relatively insensitive under our exposure conditions. Eclosing flies exposed to an O₂ enriched environment consistently possessed 2 eye abnormalities: dark eye color and altered eye shape.Supported by NSF-URP grant SP1782684 and a Summer Faculty Fellowship to Harry Nickla.     

Morphine eye-drops reduce homatropine induced mydriasis in man

Summary In 7 healthy volunteers 4% morphine eye-drops, when administered to one eye, caused a miosis limited to that eye. In 7 other healthy volunteers morphine was administered into one eye after bilateral instillation of 0.5% homatropine opthalmic drops; the eye treated with morphine and homatropine showed a mydriasis less intense than the other eye treated only with homatropine. It is suggested that topical morphine locally affects sympathetic function by inhibiting noradrenaline release into the iris neuromuscular junction.This work was partly supported by the CNR study group Pain Control. The authors wish to thank Dr Tendi of the Pharmacy of St. Maria Nuova Hospital, Florence, for the preparation of the eye-drops.     

Electron diffraction of the metallic elements in the pineal organ of a freshwater fish, Mystus vittatus (Bloch.)

By electron diffraction pattern the presence of metallic elements, particularly chromium-nickel, chromium phosphide, copper, aluminum-copper and zinc has been shown in the pineal organ of a freshwater teleost, M. vittatus. It is likely that their occurrence within the pineal is due to binding with the neurosecretory material fractions/ligands.     

Speed of in vitro reassociation of gonadotropin subunits in a teleost fish, the carp (Cyprinus carpio L.)]

Purified gonadotropin subunits of a teleost Fish, the Carp, reassociated in vitro, according to a second order rate reaction. The rate constant was temperature dependent. Compared to ovine LH, the Q10 was about three times less and the rate constant much greater (160 times for instance at 20 degrees C). The possible physiological significance of these differences is underlined.     

Precocious retina development caused by receptor cell independent light effect

In the retina of the mouth-brooding teleost Tilapia leucosticta, light causes and accelerated development of ganglion cells. This effect is presumably not mediated by receptor and interneuronal cells.     

Functional diversity of melanopsins and their global expression in the teleost retina

Melanopsin (OPN4) is an opsin photopigment that, in mammals, confers photosensitivity to retinal ganglion cells and regulates circadian entrainment and pupil constriction. In non-mammalian species, two forms of opn4 exist, and are classified into mammalian-like (m) and non-mammalian-like (x) clades. However, far less is understood of the function of this photopigment family. Here we identify in zebrafish five melanopsins (opn4m-1, opn4m-2, opn4m-3, opn4x-1 and opn4x-2), each encoding a full-length opsin G protein. All five genes are expressed in the adult retina in a largely non-overlapping pattern, as revealed by RNA in situ hybridisation and immunocytochemistry, with at least one melanopsin form present in all neuronal cell types, including cone photoreceptors. This raises the possibility that the teleost retina is globally light sensitive. Electrophysiological and spectrophotometric studies demonstrate that all five zebrafish melanopsins encode a functional photopigment with peak spectral sensitivities that range from 470 to 484 nm, with opn4m-1 and opn4m-3 displaying invertebrate-like bistability, where the retinal chromophore interchanges between cis- and trans-isomers in a light-dependent manner and remains within the opsin binding pocket. In contrast, opn4m-2, opn4x-1 and opn4x-2 are monostable and function more like classical vertebrate-like photopigments, where the chromophore is converted from 11-cis to all-trans retinal upon absorption of a photon, hydrolysed and exits from the binding pocket of the opsin. It is thought that all melanopsins exhibit an invertebrate-like bistability biochemistry. Our novel findings, however, reveal the presence of both invertebrate-like and vertebrate-like forms of melanopsin in the teleost retina, and indicate that photopigment bistability is not a universal property of the melanopsin family. The functional diversity of these teleost melanopsins, together with their widespread expression pattern within the retina, suggests that melanopsins confer global photosensitivity to the teleost retina and might allow for direct “fine-tuning” of retinal circuitry and physiology in the dynamic light environments found in aquatic habitats.     

Laminar Acetylcholinesterase localization in the optic tectum of five seawater teleosts.

The histochemical localization of acetylcholinesterase in the optic tectum of seawater teleosts shows a characteristic laminar distribution which parallels the histological structure of the nervous centre. Significant differences have been observed between Gobius and the other 4 species of teleosts examined. It seems likely that cholinergic mechanisms play an important role in the function of teleost optic tectum.     

Increase in acid phosphatase activity during fertilization of a teleost egg

Summary Acid phosphatase activity was localized at the periphery of the yolk globules in the egg of the teleost,Catostomus commersoni. In addition, a 3-fold increase in acid phosphatase activity was associated with fertilization and pronucleus formation.I thank Dr C. W. Huver for use of facilities.     

Immunofluorescent demonstration of pancreatic polypeptide (PP) in pancreas and digestive tube of bony and cartilaginous fish]

When antisera specific against bovine PP (BPP) were used, immunoreactive parenchymal cells were observed in the endocrine pancreas and in the gastro-intestinal tract of the teleost bony fish Cottus scorpius, as well as in the pancreas of the elasmobranchian cartilaginous fish Squalus acanthias. Of the two principal islets of Cottus, PP-cells were located selectively to that in the pyloric region.     

Metabolic energy requirements during teleost melanophore adaptations

Inhibition of oxidative phosphorylation by 2,4-dinitrophenol or sodium cyanide promotes complete melanosome aggregation in teleost melanophores. This aggregation is not promoted via the alpha-sympathetic receptor sites because it occurs in the presence of tolazoline hydrochloride, an alpha-receptor blocking agent. Interpretation of these results suggests metabolic energy release is required in the centrifugal direction only.     

Laminar acetylcholinesterase localization in the optic tectum of five seawater teleosts

Summary The histochemical localization of acetylcholinesterase in the optic tectum of seawater teleosts shows a characteristic laminar distribution which parallels the histological structure of the nervous centre. Significant differences have been observed betweenGobius and the other 4 species of teleosts examined. It seems likely that cholinergic mechanisms play an important role in the function of teleost optic tectum.     

Electron diffraction of the metallic elements in the pineal organ of a freshwater fish,Mystus vittatus (Bloch.)

Summary By electron diffraction pattern the presence of metallic elements, particularly chromium-nickel, chromium phosphide, copper, aluminum-copper and zinc has been shown in the pineal organ of a freshwater teleost,M. vittatus. It is likely that their occurrence within the pineal is due to binding with the neurosecretory material fractions/ligands.The technical assistance of O.N. Srivastava and financial assistance of CSIR, India, are gratefully acknowledged.     

犬高危穿透性角膜移植术后使用1％RAPA滴眼液对体内TNF-α含量的影响

目的通过观察肿瘤坏死因子-α（tumornecrosisfactor-α，TNF-α）变化情况，评价犬高危穿透性角膜移植后RAPA滴眼液抗免疫排斥反应效果。方法选择36只健康犬建立角膜高危病理模型后进行高危穿透性角膜移植手术，并分组用复方氯化钠或1％RAPA点眼，4次／d，18只未手术犬为空白对照组。同时进行外周血和角膜组织中TNF—α含量检测。结果术后7～42d复方氯化钠组和治疗组TNF-α浓度明显比对照组高（P〈0．01），在术后28d治疗组TNF-α浓度逐渐降低，复方氯化钠组仍维持较高含量。结论RAPA滴眼液能降低角膜移植手术后TNF-α含量，有效抗免疫排斥反应。     

Stretch receptors in the eye muscles of a teleost fish

Summary Extraocular muscles of a teleost fish,Girella tricuspidata, contain a predominantly phasic stretch receptor, which consists of fine beaded nerve terminals within the red portion of the muscle.The authors are grateful to Mr V. Straznik for supplying the fish, and to Mrs M. Fisher for histological assistance. Financial support for this work was received from the New Zealand Medical Research Council and the Auckland University Research Committee and University Grants Committee.