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Phylogenetic analysis of ecto-ATPase in taste buds of fishes
Abstracts
45. Comparative study on brain structures in termites Hidetoshi Isogai, Michiko Nishikawa, Fumio Yokohari, Dept. Earth System Sci., Fac. Sci., Fukuoka Univ., Fukuoka 814-0180, Japan Termites are the social Isoptera and taxonomically close to cockroaches but distant from well-known social Hymenopera such as honeybees and ants. We studied comparative morphology of brain structures in three kinds of termites: Reticulitermes speratus, Coptotermes formosanus and Hodotermopsis sjostedti. The colonies of termites comprise the reproductive and non-reproductive castes. Each caste bears distinct function in the colony. Histological preparation and three-dimensional reconstruction were performed on the brains of workers and soldiers as non-reproductive castes. Those in Hodotermopsis have compound eyes and optic lobes. On the other hand, those in Reticulitermes and Coptotermes have neither compound eyes nor optic lobes. The antennal lobe glomeruli have been counted in these termites: about one hundred glomeruli in Hodotermopsis, about ninety glomeruli in Coptotermes and about eighty glomeruli in Reticulitermes. There is no major difference between those of workers and soldiers. Other neuropils are basically the same in these termites. The external structures of brain neuropils in Hodotermopsis are similar to those in nymphal stages of the cockroach, Periplaneta americana. Volumetric analyses on prominent neuropils of the brains were also performed in these termites. We discuss the relationship between neuropil-sizes and behavioral specificities in non-reproductive castes of termites. doi:10.1016/j.cbpb.2006.10.071
46. Topographic organizations of sensory afferents of Johnston's organ in the honeybee brain Hiroyuki Ai a, Hiroshi Nishino b, Tsunao Itoh a, aDiv. Biol., Dept. Earth System Sci., Fukuoka Univ., Fukuoka 814-0180, Japan; bRes. Inst. Electronic Sci., Hokkaido Univ., Sapporo 060-0812, Japan We previously reported the afferents of JO sent axons into the dorsal lobe, the tract 6I, II and III in the dorsal lobe to have termination fields in the three neuropilar regions: the medial region of the posterior slope, dorsal region of the suboesophageal ganglion, and central region of the posterior slope, respectively. On this study the central projections of grouping of sensory neurons in JO were scrutinized in honeybees. JO somata, located in the circumference beneath the hypodermis of the pedicel, are divided into three groups based on the location: the anterior group, ventral group, and dorsal group, innervated by different nerve branches of the antennal nerve. Dye injection into individual nerve branches revealed that all groups of afferents trifurcated into the tract 6I, II and III. Among these three termination fields, only branches in the medial region of the posterior slope were characterized by thick neurites with large varicosities. Differential staining using fluorescent dyes revealed that the three groups of afferents were spatially segregated without dye-coupling, showing some degree of somatotopy. The spatial segregation was especially prominent in the medial region of the posterior slope, suggesting, its specialization for processing information from different region of the pedicel.
419
We examined short-term plasticity in wind sensitivity induced by successive airpuff stimuli to the cricket giant interneurons (GIs). When 4 air-puffs were successively applied with short intervals in 0.5, 1.0, 2.0 or 5.0 seconds, the windevoked response gradually diminished in number of action potentials. The rate of diminution in the spike number increased as the stimulus interval was shorter. In all stimulus intervals, the maximum attenuation was consistently observed in response to the second puff. To test the attenuation effects on directional sensitivity in GIs, a single air-puff from various directions was applied following 4 successive puffs from a fixed orientation. In GIs 8-1 and 9-2, the sensitivity to direction of the successive puffs showed huge decrease compared to other directions. The selective attenuation of the sensitivity to the successive-stimulus direction suggests local synaptic depression, which can result from depletion of neurotransmitter at presynaptic sites or intensive Ca 2+ elevation at activated postsynaptic sites. In GI 10-2, the directional tuning property did not change by successive stimulation, because the sensitivity to all directions equally attenuated. In this case, global Ca 2+ accumulation in whole postsynaptic dendrites may induce the attenuation of the sensitivity to all direction. doi:10.1016/j.cbpb.2006.10.073
48. Expression of NO-cGMP signaling in the olfactory center of the ant Aphaenogaster smythiesi japonica Midori Sakura a, Tetsutaro Hiraguchi a, Kyohsuke Ohkawara b, Hitoshi Aonuma a, a Neuro-cybernetics Lab., RIES, Hokkaido Univ., Sapporo 060-0812, Japan; b Division of Biological Science, Graduate School of Natural Science and Technology, Kanazawa Univ., Kanazawa 920-1192, Japan
Pheromones are important cues for inter-individual communications in particular in social insects such as ants. However, the neuronal mechanism underlying olfactory information processing, including pheromones and other environmental chemicals, is still unclear. In the silkworm moth brain, nitric oxide (NO) /cGMP cascade plays a role for information processing pathway of sexual pheromone (Seki et al, J Comp Neurol 481: 340–351). In this study, we histochemically investigated the NO/ cGMP pathways in the brain of the ant Aphaenogaster smythiesi japonica. First, we performed NADPH-diaphorase histochemistry and found putative NO releasing neurons in the antennal lobe (AL) and the central body. Next, NO-induced anticGMP immunocytochemistry was performed to examine putative NO target neurons. We found that projection neurons whose tracts connect between the AL and the mushroom body, m-ACT and l-ACT, showed strong NO-induced anticGMP immunoreactivity. Each of tracts innervates non-overlapping regions in the AL, respectively: the m-ACT originated from the most anterior part of the AL, and the l-ACT did from a large glomerulus in a distal part of the AL. Our results suggest that NO participates in the olfactory information processing and possibly involves in pheromonal processing. doi:10.1016/j.cbpb.2006.10.074
49. Phylogenetic analysis of ecto-ATPase in taste buds of fishes doi:10.1016/j.cbpb.2006.10.072
47. Short-term plasticity in wind sensitivity of the cricket giant interneurons Hiroto Ogawa a, Yoshichika Baba b, Kotaro Oka c, aDept. Biol., Fac. Med., Saitama Med. Univ., Saitama 350-0496, Japan; bDept. Biol. Sci., Coll. Liberal Arts and Sci., Univ. Illinois at Chicago, Chicago IL 60618, USA; cDept. Biosci. and Informatics, Fac. Sci. and Tech., Keio Univ., Yokohama 223-8522, Japan
Masato Kirino a, Sadao Kiyohara a, Anne Hansen b, Thomas E. Finger b, aDept. Chemistry and Bioscience, Faculty of Science, Kagoshima Univ, Kagoshima 890-0065; bDept. Cell and Devel. Biology, University of Colorado Health Sciences Center, Aurora, Colorado, USA ATP is claimed to be a crucial neurotransmitter in mammalian taste buds (Finger et al., Science 2005) and taste buds in mammals display robust ectoATPase activity, suggesting that this enzyme plays a role in inactivation of the neurotransmitter. We utilized histochemical techniques to assess whether ectoATPase activity is present in taste buds of fishes. Taste bud-bearing tissue was obtained from 6 species of fish: 2 catfish: Plotosus lineatus (barbels), Ictalurus punctatus (barbels), and goldfish,
45. Comparative study on brain structures in termites Hidetoshi Isogai, Michiko Nishikawa, Fumio Yokohari, Dept. Earth System Sci., Fac. Sci., Fukuoka Univ., Fukuoka 814-0180, Japan Termites are the social Isoptera and taxonomically close to cockroaches but distant from well-known social Hymenopera such as honeybees and ants. We studied comparative morphology of brain structures in three kinds of termites: Reticulitermes speratus, Coptotermes formosanus and Hodotermopsis sjostedti. The colonies of termites comprise the reproductive and non-reproductive castes. Each caste bears distinct function in the colony. Histological preparation and three-dimensional reconstruction were performed on the brains of workers and soldiers as non-reproductive castes. Those in Hodotermopsis have compound eyes and optic lobes. On the other hand, those in Reticulitermes and Coptotermes have neither compound eyes nor optic lobes. The antennal lobe glomeruli have been counted in these termites: about one hundred glomeruli in Hodotermopsis, about ninety glomeruli in Coptotermes and about eighty glomeruli in Reticulitermes. There is no major difference between those of workers and soldiers. Other neuropils are basically the same in these termites. The external structures of brain neuropils in Hodotermopsis are similar to those in nymphal stages of the cockroach, Periplaneta americana. Volumetric analyses on prominent neuropils of the brains were also performed in these termites. We discuss the relationship between neuropil-sizes and behavioral specificities in non-reproductive castes of termites. doi:10.1016/j.cbpb.2006.10.071
46. Topographic organizations of sensory afferents of Johnston's organ in the honeybee brain Hiroyuki Ai a, Hiroshi Nishino b, Tsunao Itoh a, aDiv. Biol., Dept. Earth System Sci., Fukuoka Univ., Fukuoka 814-0180, Japan; bRes. Inst. Electronic Sci., Hokkaido Univ., Sapporo 060-0812, Japan We previously reported the afferents of JO sent axons into the dorsal lobe, the tract 6I, II and III in the dorsal lobe to have termination fields in the three neuropilar regions: the medial region of the posterior slope, dorsal region of the suboesophageal ganglion, and central region of the posterior slope, respectively. On this study the central projections of grouping of sensory neurons in JO were scrutinized in honeybees. JO somata, located in the circumference beneath the hypodermis of the pedicel, are divided into three groups based on the location: the anterior group, ventral group, and dorsal group, innervated by different nerve branches of the antennal nerve. Dye injection into individual nerve branches revealed that all groups of afferents trifurcated into the tract 6I, II and III. Among these three termination fields, only branches in the medial region of the posterior slope were characterized by thick neurites with large varicosities. Differential staining using fluorescent dyes revealed that the three groups of afferents were spatially segregated without dye-coupling, showing some degree of somatotopy. The spatial segregation was especially prominent in the medial region of the posterior slope, suggesting, its specialization for processing information from different region of the pedicel.
419
We examined short-term plasticity in wind sensitivity induced by successive airpuff stimuli to the cricket giant interneurons (GIs). When 4 air-puffs were successively applied with short intervals in 0.5, 1.0, 2.0 or 5.0 seconds, the windevoked response gradually diminished in number of action potentials. The rate of diminution in the spike number increased as the stimulus interval was shorter. In all stimulus intervals, the maximum attenuation was consistently observed in response to the second puff. To test the attenuation effects on directional sensitivity in GIs, a single air-puff from various directions was applied following 4 successive puffs from a fixed orientation. In GIs 8-1 and 9-2, the sensitivity to direction of the successive puffs showed huge decrease compared to other directions. The selective attenuation of the sensitivity to the successive-stimulus direction suggests local synaptic depression, which can result from depletion of neurotransmitter at presynaptic sites or intensive Ca 2+ elevation at activated postsynaptic sites. In GI 10-2, the directional tuning property did not change by successive stimulation, because the sensitivity to all directions equally attenuated. In this case, global Ca 2+ accumulation in whole postsynaptic dendrites may induce the attenuation of the sensitivity to all direction. doi:10.1016/j.cbpb.2006.10.073
48. Expression of NO-cGMP signaling in the olfactory center of the ant Aphaenogaster smythiesi japonica Midori Sakura a, Tetsutaro Hiraguchi a, Kyohsuke Ohkawara b, Hitoshi Aonuma a, a Neuro-cybernetics Lab., RIES, Hokkaido Univ., Sapporo 060-0812, Japan; b Division of Biological Science, Graduate School of Natural Science and Technology, Kanazawa Univ., Kanazawa 920-1192, Japan
Pheromones are important cues for inter-individual communications in particular in social insects such as ants. However, the neuronal mechanism underlying olfactory information processing, including pheromones and other environmental chemicals, is still unclear. In the silkworm moth brain, nitric oxide (NO) /cGMP cascade plays a role for information processing pathway of sexual pheromone (Seki et al, J Comp Neurol 481: 340–351). In this study, we histochemically investigated the NO/ cGMP pathways in the brain of the ant Aphaenogaster smythiesi japonica. First, we performed NADPH-diaphorase histochemistry and found putative NO releasing neurons in the antennal lobe (AL) and the central body. Next, NO-induced anticGMP immunocytochemistry was performed to examine putative NO target neurons. We found that projection neurons whose tracts connect between the AL and the mushroom body, m-ACT and l-ACT, showed strong NO-induced anticGMP immunoreactivity. Each of tracts innervates non-overlapping regions in the AL, respectively: the m-ACT originated from the most anterior part of the AL, and the l-ACT did from a large glomerulus in a distal part of the AL. Our results suggest that NO participates in the olfactory information processing and possibly involves in pheromonal processing. doi:10.1016/j.cbpb.2006.10.074
49. Phylogenetic analysis of ecto-ATPase in taste buds of fishes doi:10.1016/j.cbpb.2006.10.072
47. Short-term plasticity in wind sensitivity of the cricket giant interneurons Hiroto Ogawa a, Yoshichika Baba b, Kotaro Oka c, aDept. Biol., Fac. Med., Saitama Med. Univ., Saitama 350-0496, Japan; bDept. Biol. Sci., Coll. Liberal Arts and Sci., Univ. Illinois at Chicago, Chicago IL 60618, USA; cDept. Biosci. and Informatics, Fac. Sci. and Tech., Keio Univ., Yokohama 223-8522, Japan
Masato Kirino a, Sadao Kiyohara a, Anne Hansen b, Thomas E. Finger b, aDept. Chemistry and Bioscience, Faculty of Science, Kagoshima Univ, Kagoshima 890-0065; bDept. Cell and Devel. Biology, University of Colorado Health Sciences Center, Aurora, Colorado, USA ATP is claimed to be a crucial neurotransmitter in mammalian taste buds (Finger et al., Science 2005) and taste buds in mammals display robust ectoATPase activity, suggesting that this enzyme plays a role in inactivation of the neurotransmitter. We utilized histochemical techniques to assess whether ectoATPase activity is present in taste buds of fishes. Taste bud-bearing tissue was obtained from 6 species of fish: 2 catfish: Plotosus lineatus (barbels), Ictalurus punctatus (barbels), and goldfish,