The avian community of the Karen Mogensen Reserve, a wealth of biodiversity within the poorly investigated and threatened environments of northwestern Costa Rica.

Despite being characterized by some of the most threatened forest ecosystems of Mesoamerica, the Nicoya Peninsula is among the least known regions of neotropical Costa Rica in terms of its birdlife. Within this region, in the framework of an ongoing international cooperation program between Italy and Costa Rica, we had the opportunity to investigate the Karen Mogensen Reserve, a protected area distinguished by the presence of a variety of habitats, including tropical dry forest and moist forest. Species richness in the Reserve was relatively high compared with similar areas in northwestern Costa Rica.

Endoreplication: a molecular trick during animal neuron evolution.

The occurrence of endoreplication has been repeatedly reported in many organisms, including protists, plants, worms, arthropods, molluscs, fishes, and mammals. As a general rule, cells possessing endoreplicated genomes are large-sized and highly metabolically active. Endoreplication has not been frequently reported in neuronal cells that are typically considered to be fully differentiated and non-dividing, and which normally contain a diploid genome.

Restraint stress alters the secretory activity of neurons co-expressing urocortin-1, cocaine- and amphetamine-regulated transcript peptide and nesfatin-1 in the mouse Edinger-Westphal nucleus.

Central stress regulatory pathways utilize various neuropeptides, such as urocortin-1 (Ucn1) and cocaine- and amphetamine-regulated transcript peptide (CART). Ucn1 is most abundantly expressed in the non-preganglionic Edinger-Westphal nucleus (npEW). In addition to Ucn1, CART and nesfatin-1 are highly expressed in neurons of the npEW, but the way these three neuropeptides act together in response to acute stress is not known.

Tyrosine and tyramine increase endogenous ganglionic morphine and dopamine levels in vitro and in vivo: cyp2d6 and tyrosine hydroxylase modulation demonstrates a dopamine coupling.

Background: The ability of animals to make morphine has been in question for the last 30 years. Studies have demonstrated that animals do contain morphine precursors and metabolites, as well as the ability to use some morphine precursors to make morphine.

Material/methods: The present study uses excised ganglia from the marine invertebrate Mytilus edulis as well as whole animals.

Endogenous morphine and ACTH association in neural tissues.

Background: Endogenous morphine and proopiomelanocortin-derived peptide-like molecules were identified in molluscan tissues, including the nervous system, supporting their ancient phylogeny. Their presence and function in "simple" animals, demonstrates their involvement in mechanisms underlying the stress response, preceding the mammalian neuroendocrine axis.

Material/methods: Immunocytochemical analysis was used to study the localization of morphine- and adrenocorticotropic hormone (ACTH)-like material in the nervous system of Planorbarius corneus, Mytilus galloprovincialis, Lymnaea stagnalis and Viviparus ater.

Endogenous morphine and codeine in the brain of non human primate.

Background: Morphine is the most used compound among narcotic analgesics. Apart from its presence in the poppy plant, morphine has been shown to be endogenously present in different tissues of mammals and lower animals.

Material/methods: The presence of endogenous morphine and codeine was investigated by Gas Chromatography/ Mass Spectrometry (GC/MS) in the brain of non human primate.

Presence and role of nitric oxide in the central nervous system of the freshwater snail Planorbarius corneus: possible implication in neuron-microglia communication.

The aim of the present study was to investigate the involvement of nitric oxide (NO) as a messenger molecule in neuron-microglia communication in the central nervous system (CNS) of the freshwater snail Planorbarius corneus. The presence of both neuronal (nNOS) and inducible nitric oxide synthase (iNOS) was studied using NADPH-diaphorase (NADPH-d) histochemistry and NOS immunocytochemistry. The experiments were performed on whole ganglia and cultured microglial cells after different activation modalities, such as treatment with lipopolysaccharide and adenosine triphosphate and/or maintaining ganglia in culture medium till 7 days.

Distribution of sensorin immunoreactivity in the central nervous system of Helix pomatia: functional aspects.

Land snails belonging to the genus Helix are commonly used to study several behaviors and their plasticity at the cellular level. Because the knowledge of sensory neurons in these species is far from being complete, we have investigated the presence and distribution in Helix pomatia central nervous system of the immunoreactivity for sensorin, a peptide specific for mechanosensory neurons in Aplysia. We found that the majority of immunopositive cells were grouped in clusters located in all the central ganglia, except for the pedal ganglion, where only a single large neuron was stained.