Distribution Pattern Of Immunoreactivity Research Articles

Early development of chick embryo respiratory nervous system: an immunohistochemical study

The extrinsic and intrinsic respiratory nervous systems receive specific contributions from the vagal and sympathetic components. Using specific markers for vagal and sympathetic structures, we studied the distribution patterns of immunoreactivity to galanin (GAL), pituitary adenylate cyclase-activating polypeptide-27 (PACAP) and the tachykinin substance P in extrinsic and intrinsic nerve of chick embryo respiratory system, during development from the very early age to hatching. All peptides studied appeared in the intrinsic and extrinsic nervous systems early. We found substance P in both the vagal and sympathetic systems, PACAP in vagal components alone and GAL mainly in the sympathetic system. The intrinsic nervous system showed high immunoreactivity for all peptides studied. These data accord with the well known early trophic functions that peptides have on the development of nervous networks and modulatory activity on the intrinsic nervous system. The GAL again proves to be the main peptide in chick embryo sympathetic respiratory system.

Immunohistochemical comparison of α- and β-synuclein in adult rat central nervous system

We investigated the immunohistochemical localization of α- and β-synuclein (αS and βS) in the adult rat CNS and compared the distribution of these proteins with that of synaptophysin (SYN), a well-established presynaptic marker. Anti-SYN, αS and βS antibodies immunolabeled the neuropil in a punctate pattern. No SYN immunoreactivity was found in the neuronal cytoplasm. In contrast, both anti-αS and βS immunostained the neuronal cytoplasm and nucleus to various extents depending on the brain region. αS-positive neurons were found in the olfactory bulb, deeper layers of the cerebral neocortex, substantia nigra and pontine nucleus. Immunoreactivity was most intense in neurons of the substantia nigra. βS-positive neurons were more widely distributed throughout the CNS: more than 50% of neurons were positive for βS in the granular cell layer of the olfactory bulb, layer IV of the cerebral cortex, CA3 of the hippocampus, basal ganglia and thalamic reticular nuclei. Moreover, there were differences among these proteins in the distribution pattern of immunoreactivity in the neuropil in some CNS regions. These findings suggest that although αS and βS are concentrated in presynaptic terminals, significant amounts of these proteins are also present in the neuronal perikarya. Furthermore, the distribution of αS-positive neurons is similar to that of intraneuronal inclusions in αS transgenic animals as well as in human α-synucleinopathies.

Distribution of PACAP-like immunoreactivity in the nervous system of oligochaeta☆

The marked similarity between the primary structures of human, other vertebrate, and the invertebrate tunicate PACAP suggests that PACAP is one of the most highly conserved peptides during the phylogeny of the metazoans. We investigated the distribution of PACAP-like immunoreactivity in the nervous system of three oligochaete (Annelida) worms with immunocytochemistry. The distribution pattern of immunoreactivity was similar in all three species ( Lumbricus terrestris, Eisenia fetida, and Lumbricus polyphemus). The cerebral ganglion contains numerous immunoreactive cells and fibers. A few cells and fibers were found in the medial and lateral parts of the subesophageal and ventral cord ganglia. In the peripheral nervous system, immunoreactivity was found in the enteric nervous system, in epidermal sensory cells, and in the clitellum.

Distribution and subcellular localization of a lysosome-associated protein in human genital organs.

The tissue distribution, preferentially in the human male genital system, and the subcellular localization of the lysosome-associated membrane protein 2 (lamp 2) was studied immunohistochemically using a mouse monoclonal antibody, 2D5. Strong immunoreactivity was present in the tubular system of the kidney, in acinar cells of salivary glands and pancreas, prostate, mammary glands, placenta and in cutaneous sweat glands. Moderate immunoreactivity was observed in cerebral neuronal cells, epidermal cells, testis, epididymis, seminal vesicle and endometrium. Very low immunoreactivity was found in liver. In some of the tissues mentioned, the distribution pattern of immunoreactivity is smooth and homogeneous, while in others it is granular and concentrated in the supra- or perinuclear cytoplasm. The subcellular distribution was studied on ultracryosections and on pre-embedding-processed chopper sections of human prostate. In the latter gland, the protein is not restricted to epithelium, but is also present in stromal cells. Ultrastructurally, the immunoreactivity in secretory cells was localized in electron-translucent vacuoles and granules, including the secretory granules. A close association with cell membranes was not generally the case. Only part of the immunoreactive material was linked to the apical plasma membrane pointing to a biosynthesis independent from an association step with the apical plasma membrane. As shown by immunoelectron microscopy and Western blotting, a high amount of lamp 2 is secreted and is found in so-called prostasomes. The findings indicate that in the human prostate most of the membrane-bound lamp 2 is released from the secretory cells, presumably in an apocrine fashion.

Immunocytochemical localization of seminal proteins in salivary and lacrimal glands of the rat.

Antibodies against 10 different secretory proteins from the accessory sex glands of the male rat were used for immunohistochemical studies of salivary and lacrimal glands from intact and castrated rats, at the light- and electron-microscopic levels. In the parotid gland, secretory acinar cells showed immunoreactivity with antibodies against prostatic binding protein, cystatin-related peptide and acid phosphatase (isoenzyme pI 8.0; 5.6) typical of ventral prostate, and seminal vesicle secretion VI. Western blotting analysis indicated that immunoreactivity against prostatic binding protein was attributable to a subunit, presumably C3. Acid phosphatase pI 5.6 showed a molecular weight of 66 kDa, which is at variance with the prostatic form. Immunoreactivity for secretory transglutaminase, derived from the coagulating gland, was restricted to myoepithelial and stromal cells. In castrated animals, the immunoreactivity of acinar cells was reduced to the background level, whereas stromal transglutaminase immunoreactivity was unaltered. The distribution pattern of immunoreactivity for the proteins mentioned was almost identical in the lacrimal gland. Significant differences were however observed in the immunoreactivity of the inframandibular gland, where serous glandular cells were non-immunoreactive for seminal proteins, with the exception of acid phosphatase isoenzyme pI 8.0. Granules present in the convoluted granular ducts were immunoreactive particularly for acid phosphatase (isoenzyme pI 5.6) but much less for cystatin-related peptide; immunoreactivity was reduced after castration. The straight portion of the inframandibular duct system was immunoreactive for transglutaminase, but no influence of castration was visible. The distribution of immunoreactivity for seminal proteins present in the salivary and lacrimal glands and the pronounced androgen-dependence of their expression point to functional relationships of the respective proteins at both glandular sites.

Tachykinin multiplicity in rat central nervous system as studied using antisera raised against substance P and neurokinin A

Antisera were raised in rabbits against the tachykinins neurokinin A (NKA) and substance P (SP). All NKA-antisera tested cross-reacted markedly with NKB, kassinin and eledoisin in radioimmunoassay (RIA), but virtually not with SP and physalaemin. Also when used for immunohistochemistry, one of the NKA-antisera was found to be virtually without cross-reactivity with SP. The most specific SP-antiserum did not cross-react with NKA but to some extent with NKB at the immunohistochemical level. Using these two antisera, the same distribution pattern of immunoreactivity was seen in both the rat substantia nigra and dorsal spinal cord. In neutral extracts of the substantia nigra, all NKA-antisera used for RIA detected a major component which eluted at the position of NKA in reverse phase high performance liquid chromatography, while no or only little immunoreactivity was detected at the position of NKB. A major component of substance P-like immunoreactivity (SPLI) co-eluting with SP and one or two minor SPLI-components were also detected in these extracts. An SP-antiserum, which cross-reacted markedly with physalaemin, detected an additional rather prominent component. In neutral water extracts of dorsal spinal cord the component detected with the NKA-antisera at the position of NKB, as well as one of the SPLI-components not eluting in the position of SP, were much more prominent than in the corresponding extracts of substantia nigra. In acetic acid extracts of both tissues, only one major SPLI-component co-eluting with SP could be detected, while only very small amounts of immunoreactivity eluting at the position of NKA and NKB (dorsal spinal cord only) could be detected using the NKA-antisera. The present results illustrate the importance of the extraction method used in immunochemical studies and demonstrate that the relative proportions of various tachykinins are markedly different in the rat substantia nigra and dorsal spinal cord.