Multiplicity of Opioidergic Pathways Related to Cardiovascular Innervation: Differential Contribution of All Three Opioid Precursors

The endogenous opioid family consists of the three precursors proenkephalin (proenkephalin A), prodynorphin (proenkephalin B), and proopiomelanocortin (POMC), from which various opioid and nonopioid peptides can be processed, apparently in a tissue-specific manner (cf. Civelli et al. 1984; Goldstein 1984; Herz 1984; Udenfriend and Kilpatrick 1984; Civelli et al. 1985; Khachaturian et al. 1985; Kosterlitz 1985). Their distribution in areas of the CNS which are involved in cardiovascular regulation is well documented. The biochemistry and functions of endocrine (pituitary and adrenal) opioids have also been well characterized (cf. Millan and Herz 1985). The conception that endocrine and CNS o…

Chapter 21 Immunohistochemical evidence for a co-transmitter role of opioid peptides in primary sensory neurons

Publisher Summary The purpose of this chapter is to answer several open questions regarding opioid peptides by using a highly sensitive light microscopic (LM) immunohistochemical approach. The chapter mentions the immunohistochemical evidence for a co-transmitter role of opioid peptides in primary sensory neurons. It introduces the concept that there is a functionally important tandem constellation of transmitters in a specific nociceptive population of primary sensory afferents consisting of (1) an inhibitory transmitter family, the opioid peptides, and (2) an excitatory transmitter family, the tachykinins. Small-diameter primary sensory neurons not only transmit nociceptive messages to ce…

Granulomatous mycosis fungoides, a rare subtype of cutaneous T-cell lymphoma

Granulomatous mycosis fungoides (GMF) is an unusual histologic subtype of cutaneous T-cell lymphoma.1 The diagnosis of GMF is usually established after observation of a granulomatous inflammatory reaction associated with a malignant lymphoid infiltrate. Epidermotropism, a clue to diagnosis in classical mycosis fungoides (MF) may be absent in about 47% of cases of GMF.2 In some instances, the granulomatous component may be intense and obscures the lymphomatous component of the infiltrate.1 There are no distinctive clinical patterns associated with GMF.1, 3

Chromogranin A in the Mammalian Merkel Cell: Cellular and Subcellular Distribution

Chromogranin-A (CGA), which accounts for more than half the soluble matrix protein in secretory granules of various neuroendocrine cells, has a wide spectrum of potential biological roles and is considered an important marker of the diffuse neuroendocrine system (DNES). Light and electron microscopic immunohistochemistry of mammalian skin revealed that Merkel cells are exclusively CGA-immunoreactive (ir) and that the immunoreaction is localized in the secretory granules. This finding supports the classification of the Merkel cell as a member of the DNES. The CGA immunoreactivity was restricted to Merkel cells of pigs and humans. In human embryonic skin, CGA was expressed in Merkel cells as …

Immunohistochemical analysis of chromogranin A and multiple peptides in the mammalian Merkel cell: further evidence for its paraneuronal function?

By the use of light microscopic immunohistochemistry, epidermal Merkel cells have been examined for the coexistence of some neuropeptides and chromogranin A (CGA). Peptide and CGA-immunophenotypes were similar in adult Merkel cells but variable in fetal skin, where CGA preceded the expression of peptides which were partly expressed only in a subpopulation of Merkel cells from hair follicles. Thus, only Substance P (SP) and calcitonin gene-related peptide (CGRP) were expressed in a subpopulation of Merkel cells from hair follicles. There were similar Merkel cell densities visualized on consecutive paraffin sections by the use of antisera against peptides, CGA and cytokeratin offering useful …

First International Merkel Cell Symposium, Heidelberg, Germany

Chapter 20 Multiple messenger candidates and marker substances in the mammalian Merkel cell – axon complex: a light and electron microscopic immunohistochemical study

Publisher Summary This chapter discusses multiple messenger candidates and marker substances in the mammalian merkel cell—axon complex. According to the APUD theory, cells of the diffuse neuroendocrine system (DNES) are essentially characterized by containing amines, peptides and marker substances like neuronspecific enolase (NSE) and chromogranin A (CGA). By the comparison of the histotopography of immunostained peptides, CGA and neuroendocrine markers, there was an expectation to find out the most appropriate immunohistochemical marker of the Merkel cell and to get further insight into the complex chemo-anatomy and possible functional spectrum of the Merkel cell -axon complex at various d…

Electron microscopic immunogold cytochemistry reveals chromogranin A confined to secretory granules of porcine Merkel cells

By ultrastructural immunohistochemistry using the immunogold technique, immunoreactive (ir) Chromogranin A (CGA) was found to be confined to the secretory vesicles of porcine Merkel cells. CGA was present predominantly in the periphery of the electron-dense core and on the clear halo. These findings indicate that CGA is a regular constituent of Merkel cell secretory granules but probably not exclusively responsible for their electron opacity.