摘要:

AbstractThe muscle fibers of the pectoralis (M. pectoralis pars thoracicus) of a male and a female ostrich (Struthio camelus) and a male and a female emu (Dromaius novaehollandiae) were studied histochemically for succinate dehydrogenase and myofibrillar adenosine triphosphatase. Slow‐tonic (ST), fast‐twitch oxidative‐glycolytic (FOG) and fast‐twitch glycolytic (FG) fibers were approximately equal in number and distribution in the emu pectoralis examined. In the ostriches, both predominantly FG and approximately equal areas, were present. ST fibers were significantly (P≤ 0.05) larger than the similarly (P≥ 0.05) sized FG and FOG fibers in the female ostrich and emus. In the male ostrich ST fibers were smaller (P≤ 0.05) than FG fibers, neither of which were significantly (P≥ 0.05) different from FOG fibers. The ratites have the greatest percentage and widest distribution of ST fibers found in any avian pectoralis studied to date. This could represent the ancestoral avian pectoralis, neoteny or an effect of flightlessness. ST fibers are used in the maintenance of posture, which is probably the main role of the pectoralis in the emu. The predominantly FG areas of the ostrich are indicative of an additional function, namely, behavioural display. Sexual dimorphism in the ostrich pectoralis is str

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1985.tb00839.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractImmunofluorescence tests with antisera to various peptides reveal the presence of a FMRFamide‐like peptide in neurons of hydromedusae belonging to three orders. An avian pancreatic polypeptide‐like peptide may also be present in certain neurons. Distribution of FMRFamide‐like immunoreactivity (Fa‐IR) has been studied inProboscidactyla(O. Limnomedusae),PhialidiumandAequorea(O. Leptomedusae) andAglantha(O. Trachymedusae). These findings are compared with results obtained withPolyorchis(O. Anthomedusae) by Grimmelikhuijzen and Spencer [J. comp. Neurol.230, 361 (1984)]. All species show Fa‐IR neurons in the tentacles linked by interconnecting neurites running in the outer marginal nerve ring. A Fa‐IR plexus is present in the manubrium and, except inAglantha, this system merges with a plexus associated with the subumbrellar radial muscles. As inPolyorchis, the swimming motor neurons are unstained. In contrast to this species, only a small percentage of the neurites composing the nerve rings are stained. The giant axons ofAglanthashow no Fa‐IR. The cnidothylaces ofProboscidactylacontain neurons reacting with antisera to FMRFamide and APP. Present evidence suggests that in hydromedusae Fa‐IR is confined to distinct subsets of neurons. These appear to be either sensory units or units supplying smooth muscles, but they are not involved in the innervation of s

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1985.tb00840.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractThe lip structures termed labial probolae, characteristic for the subfamily Acrobelinae, and the anterior sense organs have been studied by electron microscopy. The labial probolae consist of an amorphous tissue with denser strengthenings. They do not contain any sensory structures or musculature. The anterior sense organs consists of: (1) six inner labial sensilla, each with one receptor ending in a pore on a papilla; (2) six outer labial sensilla, each with one receptor ending in the cuticle; (3) four cephalic sensilla, each with two receptors, one ending in a pore on a papilla and the other in the cuticle; (4) two amphids, each with 12 sensory neurons basally; (5) accessory sensilla ventro‐laterally. The combination of several chemoreceptive anterior sensilla and the morphological diversity of the labial probolae within the subfamily may aid in the utilization of different soil microhabitat

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1985.tb00841.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY

摘要:

AbstractGlial cells of abdominal ganglia of crayfish have been studied by transmission electron microscopy. Four cell types can be defined: (1) perivascular glial cells, close to the vascular spaces; (2) perineuronal glial cells, the processes of which ensheathe neuron perikarya; (3) adaxonal glial cells ensheathing axons; (4) neuropilar glial cells, associated with synapsing terminals in the neuropile.Neuropilar glia, adaxonal glia and the system formed by perineuronal and perivascular glia separate different functional zones of the neurons from the hemolymph or the electron dense extracellular matrix. These glial arrangements could play a similar role in hemato‐neuronal transport. Gap‐like junctions between glia and neuron cell bodies are frequent and could be involved in direct triggering of glial activities related to neur

ISSN:0001-7272    

DOI:10.1111/j.1463-6395.1985.tb00842.x

出版商:Blackwell Publishing Ltd    

年代:1985

数据来源: WILEY