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Ontogenetic development of the pineal organ, parapineal organ, and retina of the three-spined stickleback, Gasterosteus aculeatus L. (Teleostei) - Development of photoreceptors

The ontogenetic developments of the pineal organ, parapineal organ, and retina were studied by the use of light and electron microscopy in embryos and fry of the teleost, Gasterosteus aculeatus, from 60 to 168 h after fertilization. Sixty to 66 h after fertilization, the primordium of the pineal complex is discernible in the diencephalic roofplate; the parapineal anlage is located rostral to the p

The pineal complex of the three-spined stickleback, Gasterosteus aculeatus L. - A light-, electron microscopic and fluorescence histochemical investigation

The pineal complex of the three-spined stickleback (Gasterosteus aculeatus L.) was investigated by light and electron microscopy, as well as fluorescence histochemistry for demonstration of catecholamines and indolamines. The pineal complex of the stickleback consists of a pineal organ and a small parapineal organ situated on the left side of the pineal stalk. The pineal organ, including the entir

The Effect of Ambiguous Question Wording on Jurors’ Presumption of Innocence

Research suggests that jurors misunderstand the presumption of innocence. However, past studies have not asked participants to estimate the defendant’s probability of guilt, setting aside the fact of charge and indictment. We conduct two studies to explore the impact of this question wording on estimates of the probability of guilt/innocence by jury-eligible Mturk workers. In Experiment 1 (N = 275

Neural elements in the pineal complex of the frog, rana esculenta, II : Gaba-immunoreactive neurons and FMRFamide-immunoreactive efferent axons

The photosensory pineal complex of anurans comprises an extracranial part, the frontal organ, and an intracranial part, the pineal organ proper. Although the pineal organ functions mainly as a luminosity detector, the frontal organ may monitor the relative proportions of short and intermediate/long wavelengths in the ambient illumination. The major pathway of information processing in the pineal a

Role of the pineal organ in the photoregulated hatching of the Atlantic halibut

The timing of hatching in the Atlantic halibut (Hippoglossus hippoglossus) has been suggested to be regulated by environmental light conditions. However, the photosensory organ that perceives the triggering light has not been identified. In the present study, we investigated the morphogenesis of the pineal organ and the neurochemical differentiation of photoreceptors in the pineal organ and the re

Opsin-like immunoreaction in the retinae and pineal organs of four mammalian species

Opsin-like immunoreactivity was observed in the retinae and pineal organs of the mouse, rat and guinea pig, and the pineal organ of the cat. In the retina the immunoreaction was restricted to photoreceptor cells, which displayed immunostaining in their perikarya and outer and inner segments. Distinct pinealocytes endowed with characteristic processes were labelled in the pineal organs of the mouse

Pinealocyte projections into the mammalian brain revealed with S-antigen antiserum

Neural processes from mammalian pinealocytes have been discovered in several brain areas. These processes were visualized immunocytochemically in the Djungarian hamster, Phodopus sungorus, with an antiserum against bovine retinal S-antigen and traced as far as the region of the posterior commissure and habenular nuclei. This result indicates that pineal-to-brain connections exist in the mammal, an

Dark and light adaptation of pineal photoreceptors

Abstract Dark and light adaptation of pineal photoreceptors was studied in the isolated pineal organ of the rainbow trout, Salmo gairdneri. After intracellular recording, the photoreceptors were iontophoretically injected with Lucifer yellow CH or with horseradish peroxidase for morphological characterization. Pineal photoreceptor cells responded to light with a hyperpolarization whose amplitude w

Photoreceptor responses to light in the isolated pineal organ of the trout, Salmo gairdneri

Photoreceptor potentials were recorded intracellularly from the isolated pineal organ of the teleost, Salmo gairdneri, maintained in tissue culture medium for 2-20 h. After electrophysiological characterization the photoreceptor cells were iontophoretically injected with Lucifer Yellow or with horseradish peroxidase for subsequent morphological identification. A brief flash of light elicited a hyp

Action of γ-aminobutyric acid (GABA) in the isolated photosensory pineal organ

The effect of GABA (γ-aminobutyric acid), its agonists (muscimol, baclofen) and antagonist (bicuculline) on pineal ganglion cells of the luminosity type were studied in the isolated, superfused pineal organ of the rainbow trout, Oncorhynchus mykiss. Extracellular recordings revealed that GABA added through the superfusion medium caused a clear alteration of the actvity of projecting neurons, which

Temporal disparity in pineal and retinal ontogeny

The development of photoreceptors and two putative neurotransmitter systems in the pineal organ and retina was studied during embryogenesis in the three-spined stickleback Gasterosteus aculeatus L. The investigation was performed by aid of immunocytochemistry using well characterized antisera to the retinal proteins α-transducin (TDα) and S-antigen (SA) (photoreceptor-markers), antisera against l-

Postsmolt change in numbers of acetylcholinesterase-positive cells in the pineal organ of the Pacific coho salmon

We have examined the occurrence of acetylcholinesterase (AChE)-positive cells in the pineal organ of different developmental stages of the Pacific coho salmon. Large numbers of AChE cells were present in fresh-water living alevins, in all stages of presmolts (n=307-544), and in adult spawners (n=696-1774) whereas seawater-living postmolts displayed a total lack of labeled cells. The AChE-reactive

Neural projections of the pineal organ in the larval sea lamprey (Petromyzon marinus L.) revealed by indocarbocyanine dye tracing

The distribution of the central neural connections of the pineal organ of the larval sea lamprey was investigated by means of anterograde and retrograde tracing with the fluorescent lipophilic dye. DiI (1,1′-dioctadecyl 3,3,3′,3′-tetramethylindocarbocyanine perchlorate). Pinealofugal projections are well developed in larvae, extending from the posterior commissure into the diencephalon and mesence

Central neural connections of the pineal organ and retina in the teleost Gasterosteus aculeatus L.

The relations of the central neural connections of the pineal organ to those of the retinae of the lateral eyes were investigated in the three‐spined stickleback, Gasterosteus aculeatus L. (Teleostei), by anterograde and retrograde transport of horseradish peroxidase (HRP). HRP was applied to the crushed pineal stalk and/or injected into the left or the right eye. Both pineal and retinal efferents

Pineal neurons projecting to the brain of the rainbow trout, Salmo gairdneri Richardson (Teleostei) - In-vitro retrograde filling with horseradish peroxidase

The morphology of intrapineal neurons that give rise to the pineal tract and project to the brain in the rainbow trout was visualized by the use of neuronal backfilling with horseradish peroxidase (HRP). The tracing was performed on excised pineal organs under in-vitro conditions at 4° C, with filling times ranging from 6 to 24 h. Large multipolar, bipolar and unipolar neurons were visualized in t

Putative cholinergic elements in the photosensory pineal organ and retina of a teleost, Phoxinus phoxinus L. (Cyprinidae) - Distribution of choline acetyltransferase immunoreactivity, acetylcholinesterase-positive elements and pinealofugally projecting neurons

Putative cholinergic neurons in the photosensory pineal organ of a cyprinid teleost, the European minnow, were studied by use of choline acetyltransferase (ChAT) immunocytochemistry and acetylcholinesterase (AChE) histochemistry. Pinealofugally projecting neurons were visualized using retrograde HRP-filling through their cut axons. For comparison, the distribution of choline acetyltransferase immu

Intracellular staining of physiologically identified photoreceptor cells and hyperpolarizing interneurons in the teleost pineal organ

The directly photosensory pineal organ of the rainbow trout functions primarily as a luminance detector. Its neutral output reflects the level of ambient illumination in an almost linear fashion over several orders of magnitude. It may thus transmit information about the daily light-dark cycle to central projection targets in the brain, and exert an important control over putative central oscillat

Signal processing in a simple vertebrate photoreceptor system : the teleost pineal organ.

The integrating circuitry and efferent pathways for neural signals evoked in the photosensory pineal organ by changes in ambient illumination have been investigated by a multidisciplinary approach. Intrapineal efferent neurons were identified by means of retrograde filling with horseradish peroxidase (HRP). In addition to several types of neurons, photoreceptor cells that emitted axons to the brai