RESUMO
Serial histological sections of the interatrial septum and basal heart vessels of the weaned and juvenile white-belly opossum (Didelphis albiventris) were obtained in order to study the presence of paraganglia and their content of regulatory peptides and serotonin. Paraganglion groups were mapped between the aorta and pulmonary arteries and close to the bifurcation of the pulmonary trunk and were found to contain cells with immunoreactivity to serotonin and to the neuroendocrine markers PGP 9.5 and NSE. When these paraganglia were tested for immunoreactivity to a battery of regulatory peptides, all were found to be positive for methionine-enkephalin, leucine-enkephalin and galanin. The hypothesis is raised that these peptides and serotonin, besides catecholamines, produced by these paraganglia may play a physiological role in the functions of the cardiovascular system of the white-belly opossum.
Assuntos
Sistema Cardiovascular/crescimento & desenvolvimento , Encefalinas/isolamento & purificação , Gambás/fisiologia , Paragânglios Cromafins/química , Serotonina/isolamento & purificação , Animais , Imuno-Histoquímica , Microtomia , Peptídeos/isolamento & purificação , DesmameRESUMO
The surface morphology and organization of the neuromuscular system in Cercaria caribbea LXXI are investigated using scanning and transmission electron microscopy, respectively. Direct and indirect (sarconeural) nerve-muscle junctions are identified in the cercarial tail. Synaptic vesicles at the direct neuromuscular junction suggest cholinergic and aminoacidergic transmission. Those at the sarconeural junctions suggest catecholaminergic and/or serotonergic transmission. Acetylcholinesterase and non-specific cholinesterases were found in high concentrations in the proximal and distal tail. Flourescence histochemistry showed primary catecholamines and 5-HT in the body and tail. 5-HT in the tail may represent a slowly depleted store, perhaps associated with energy availability and utilization. (AU)
Assuntos
Parasitos/ultraestrutura , Junção Neuromuscular/fisiologia , Microscopia Eletrônica , Microscopia Eletrônica de Varredura , Colinesterases , Aminas Biogênicas , Músculos/anatomia & histologia , Serotonina/isolamento & purificação , Catecolaminas/isolamento & purificação , FluorescênciaRESUMO
Sixty collections of ten species referred to three families of the Agaricales have been analyzed for the presence of baeocystin by thin-layer chromatography. Baeocystin was detected in collections of Psilocybe, Conocybe, and Panaeolus from the U.S.A., Canada, Mexico, and Peru. Laboratory cultivated fruitbodies of Psilocybe cubensis, P. semilanceata, and P. cyanescens were also studied. Intra-species variation in the presence of decay rate of baeocystin, psilocybin and psilocin are discussed in terms of age and storage factors. In addition, evidence is presented to support the presence of 4-hydroxytryptamine in collections of P. baeocystis and P. cyanescens. The possible significance of baeocystin and 4-hydroxytryptamine in the biosynthesis of psilocybin in these organisms is discussed.