title: Light and electron-microscopic study of leucine enkephalin immunoreactivity in the cat claustrum.
abstract: The claustrum is a complex telencephalic structure owing to its reciprocal connectivity with most--if not all--cortical areas. However, there is a paucity of data in the literature concerning its histochemical components, including opioid peptide neurotransmitters. The aim of the present study was to examine the morphology, distribution and ultrastructure of leucine-enkephalin-immunoreactive (Leu-enk-ir) neurons and fibers in the dorsal claustrum (DC) of the cat. Seven healthy, adult male and female cats were used in our study. All animals received humane care. They were irreversibly anesthetized and transcardially perfused with fixative. Brains were removed, postfixed, blocked and sectioned. Sections were incubated with polyclonal anti-Leu-enk antibodies using the Avidin-Biotin-Peroxidase Complex method. Leu-enk-ir neurons and fibers were distributed throughout the DC. Some of the neurons were lightly-stained, while others were darkly-stained. Light-microscopically, they varied in shape: oval, fusiform, multipolar and irregular. With regard to size, they were categorized as small (15 μm or less in diameter), medium (16-20 μm in diameter) and large (21 μm or more in diameter). No specific pattern of regional distribution was found. On the electron microscope level, immunoproduct was observed in neurons, dendrites and terminal boutons. Different types of Leu-enk-ir neurons differ in their ultrastructural features, including two types of synaptic boutons. No gender-specific features were observed. In conclusion, it is our hope that our study will serve to contribute to a better understanding of the functional neuroanatomy of the DC in the cat, and that it can be extrapolated and applied to other mammals, including humans.
authors.affiliation: Department of Anatomy and Histology, Medical University, 1431, Sofia, Bulgaria.
authors.forename: Dimka
authors.initials: D
authors.lastname: Hinova-Palova
authors.forename: Lawrence
authors.initials: L
authors.lastname: Edelstein
authors.forename: Vassil
authors.initials: V
authors.lastname: Papantchev
authors.forename: Boycho
authors.initials: B
authors.lastname: Landzhov
authors.forename: Lina
authors.initials: L
authors.lastname: Malinova
authors.forename: Daniela
authors.initials: D
authors.lastname: Todorova-Papantcheva
authors.forename: Minko
authors.initials: M
authors.lastname: Minkov
authors.forename: Adrian
authors.initials: A
authors.lastname: Paloff
authors.forename: Wladimir
authors.initials: W
authors.lastname: Ovtscharoff
mesh_terms: D000818:Animals; D001479:Basal Ganglia / Q000378:metabolism*; D002415:Cats; D004743:Enkephalin, Leucine / Q000378:metabolism*; D005260:Female; D007150:Immunohistochemistry; D008297:Male; D008854:Microscopy, Electron; D009474:Neurons / Q000378:metabolism / Q000648:ultrastructure; D051381:Rats
chemical_list: D004743:Enkephalin, Leucine