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21.
22.
Scott L. Hooper Michael B. O'Neil Robert Wagner John Ewer Jorge Golowasch Eve Marder 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》1986,159(2):227-240
Summary The muscles of the pyloric region of the stomach of the crab,Cancer borealis, are innervated by motorneurons found in the stomatogastric ganglion (STG). Electrophysiological recording and stimulating techniques were used to study the detailed pattern of innervation of the pyloric region muscles. Although there are two Pyloric Dilator (PD) motorneurons in lobsters, previous work reported four PD motorneurons in the crab STG (Dando et al. 1974; Hermann 1979a, b). We now find that only two of the crab PD neurons innervate muscles homologous to those innervated by the PD neurons in the lobster,Panulirus interrruptus. The remaining two PD neurons innervate muscles that are innervated by pyloric (PY) neurons inP. interruptus. The innervation patterns of the Lateral Pyloric (LP), Ventricular Dilator (VD), Inferior Cardiac (IC), and PY neurons were also determined and compared with those previously reported in lobsters. Responses of the muscles of the pyloric region to the neurotransmitters, acetylcholine (ACh) and glutamate, were determined by application of exogenous cholinergic agonists and glutamate. The effect of the cholinergic antagonist, curare, on the amplitude of the excitatory junctional potentials (EJPs) evoked by stimulation of the pyloric motor nerves was measured. These experiments suggest that the differences in innervation pattern of the pyloric muscles seen in crab and lobsters are also associated with a change in the neurotransmitter active on these muscles. Possible implications of these findings for phylogenetic relations of decapod crustaceans and for the evolution of neural circuits are discussed.Abbreviations
ACh
acetylcholine
-
Carb
carbamylcholine
-
cpv
muscles of the cardio-pyloric valve
-
cpv7n
nerve innervating muscle cpv7
-
cv
muscles of the ventral cardiac ossicles
-
cv1n
nerve innervating muscle cvl
-
cv2n
nerve innervating muscle cv2
-
EJP
excitatory junctional potential
-
IC
inferior cardiac neuron
-
IV
inferior ventricular neuron
-
IVN
inferior ventricular nerve
-
LP
lateral pyloric neuron
-
LPG
lateral posterior gastric neuron
-
lvn
lateral ventricular nerve
-
mvn
medial ventricular nerve
-
p
muscles of the pylorus
-
PD
pyloric dilator neuron
-
PD
in
intrinsic PD neuron
-
PD
ex
extrinsic PD neuron
-
pdn
pyloric dilator nerve
-
PY
pyloric neuron
-
pyn
pyloric nerve
-
STG
stomatogastric ganglion
-
VD
ventricular dilator neuron 相似文献
23.
Cells of a mutant in vivo subline of the Ehrlich-Lettré mouse ascites tumour (ELAT) were converted to growth in suspension culture. Kinetic analysis revealed the selective character of the conversion process; without a detectable adaptation period, a fraction of about 2 × 10-5 of the explanted cells continued to grow in vitro. the resulting, mutant Ehrlich-Lettré ascites cell strain was designated HD33 and propagated uninterruptedly from 1974 on. the corresponding in vivo ELAT subline HD33 was derived from the HD33 ascites cell strain by intraperitoneal retransplantation. In HD33 cell suspension cultures, the population doubling time, the average intermitotic interval, as determined by videomonitoring, and the average duration of the cell cycle, as determined from percentage of labelled mitoses (PLM) data, were all measured at 15 hr. Cell loss and quiescent compartments were insignificant. the duration of the G1 phase was effectively zero. Both PLM data and [3H]/[14C] thymidine double-labetling measurements revealed an S-phase duration of between 11 and 12 hr. the G2 phase lasted 3–5 hr. The HD33 strain differs from comparable suspension strains of wild-type Ehrlich ascites cells in the insignificant role of density-dependent inhibition in growth, and the striking prolongation of the S phase which is associated with an excessive, cytoplasmic storage of glycogen by the mutant cells. 相似文献
24.
A. Mouras A. Lutz 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1983,64(4):283-288
Summary The determination of partial genotype, B/b and D/d, for coat colour in dogs, from phenotypic observations, is discussed. It is shown that the probability of a given genotype can be reliably determined where multiple observations on the mating of a given dog are available. 相似文献
25.
Antigen-induced lymphomagenesis: identification of a murine B cell lymphoma with known antigen specificity 总被引:14,自引:0,他引:14
L W Arnold N J LoCascio P M Lutz C A Pennell D Klapper G Haughton 《Journal of immunology (Baltimore, Md. : 1950)》1983,131(4):2064-2068
CH12, a murine B cell lymphoma derived in B10 H-2aH-4bp/Wts mice after transfer of SRBC hyperimmunized spleen cells into an adult-thymectomized, sublethally irradiated, syngeneic recipient, is demonstrated to bear surface IgM specific for a determinant found on SRBC and ChRBC. The Ig specificity has been demonstrated by rosetting assays and complement-dependent hemolysis. The removal of CH12 surface IgM by capping with anti-mu or with anti-CH12 idiotype, but not with anti-gamma or with irrelevant anti-idiotype, eliminated the formation of rosettes between CH12 and SRBC or ChRBC. The absorption of CH12 Ig produced in vitro, with either SRBC or ChRBC but not with HRBC, removed all hemolysin activity against SRBC, demonstrating that only one CH12 product was responsible for the reactivity with both SRBC and ChRBC. CH12 has a surface phenotype of a relatively mature B cell expressing surface Ig (IgM-mu,kappa) and la antigens, but lacking Thy-1 or detectable Fc or C3 receptors. CH12 also expresses the antigen Lyt-1. Growth of CH12 in vivo or in vitro results in the generation of up to 3% direct PFC and serum hemolysin, which shows that CH12 is not irretrievably "frozen". The generation of PFC and serum hemolysin is associated with increased population density, and the rate of PFC and serum hemolysin accumulation cannot be explained by simple cell division. A continuously secreting hybridoma derived from CH12 was used to purify the CH12 IgM to facilitate studies of protein sequence and idiotype. 相似文献
26.
A new method of calculation, based on a direct fitting of the protein fluorescence intensity observed upon coenzyme binding (H.-P. Lutz, unpublished results), is used to study the negative cooperative behavior of glyceraldehyde-3-phosphate dehydrogenase from sturgeon muscle. The calculation procedure simultaneously elaborates data obtained for four different protein concentrations, and it is able to compare different models by computing the minimal and critical sum of squares. Using this approach, it is shown that the induced-fit model [Koshland, D. E., Jr., Nemethy, G., & Filmer, D. (1966) Biochemistry 5,365] and the dimer of dimer model [Malhotra, O. P., & Bernhard, S. A. (1968) J. Biol. Chem. 243, 1243-1252] can both be applied for explaining the negative cooperativity observed upon coenzyme binding to sturgeon glyceraldehyde-3-phosphate dehydrogenase. In addition to the progressive modification of the binding affinity during ligand binding, different maximal fluorescence quenchings for the binding steps must be postulated; and furthermore, the binding capability decreases by decreasing the protein concentration. The fact that the induced-fit model can also be applied is rather in contradiction with the view generally accepted of a dimer of dimer structure of sturgeon glyceraldehyde-3-phosphate dehydrogenase. By use of the same approach, nicotinamide 8-bromoadenine dinucleotide is shown to bind to glyceraldehyde-3-phosphate dehydrogenase from sturgeon in a negative cooperative manner. 相似文献
27.
J.H. Southard N.Chr. Van Der Laan M. Lutz G.S. Pavlock J.P. Belzer F.O. Belzer 《Cryobiology》1983,20(4):395-400
The effect of temperature on the rate of ADP-stimulated respiration of mitochondria from dog, rabbit, pig, and human kidney cortex mitochondria was plotted according to the Arrhenius relationship. The temperature at which the plot demonstrated a break was at 15 °C for mitochondria from dog, pig, and human kidneys. The discontinuity occurred at 10 °C or less for mitochondria from rabbit kidneys. This difference suggests that mitochondria from rabbit kidneys undergo a lipid-phase transition at lower temperatures than for other species commonly used in experimental renal preservation. The implications of this difference suggest caution in using results obtained with rabbit kidneys for comparison to results obtained from hypothermic renal preservation of other species kidneys. Apparent fluidization of dog kidney mitochondrial membranes with adamantine abolished the discontinuity in the Arrhenius plot. 相似文献
28.
Hg ++ - a DCMU independent electron acceptor of photosystem II 总被引:3,自引:0,他引:3
D Miles P Bolen S Faraq R Goodin J Lutz A Moustafa B Rodriquez C Weil 《Biochemical and biophysical research communications》1973,50(4):1113-1119
Mercuric chloride functions as a direct electron acceptor from the quencher of fluorescence in Photosystem II. The photoreduction of ferricyanide, dichlorophenol-indophenol or methyl viologen is inhibited by mercuric ion while oxygen evolution is uneffected. Mercuric chloride supported oxygen evolution (mercury Hill reaction) is not prevented by DCMU or other similar electron transport inhibitors. 相似文献
29.
Lutz Vollrath 《Cell and tissue research》1969,99(1):146-152
Zusammenfassung In der Neurohypophyse fetaler und neugeborener Ratten entsteht die Mehrzahl der synaptischen Bläschen aus Erweiterungen der Neurotubuli. Ferner können pinocytotische Bläschen als synaptische Vesikel imponieren. Die Bläschenbildung aus Membranen von Elementargranula (vgl. Herlant, 1967) tritt dagegen in den Hintergrund. Ein Auftreten von Vesikeln im Innern von Elementargranula wurde nicht beobachtet.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
The origin of synaptic vesicles in neurosecretory axons
Summary In the neurohypophysis of fetal and newborn rats the majority of synaptic vesicles originate from dilatations of neurotubuli. Moreover, pinocytotic invaginations give rise to synaptic vesicles. Evaginations of elementary granule membranes, as described by Herlant (1967), are seldom to be found and do not seem to play an important role in the formation of synaptic vesicles. The occurrence of vesicles within elementary granules was not observed.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
30.
Further Studies on the Phage Sensitivity and the Determination of Phytopathogenic Pseudomonas spp. 总被引:1,自引:1,他引:0
Eve Billing 《Journal of applied microbiology》1970,33(3):478-491