Peptidergic neurons

Moragues, N., Ciofi, P., Lafon, P., Tramu, G., Garret, M. (2003). GABAa receptor epsilon subunit expression in identified peptidergic neurons of the rat hypothalamus. Brain Res. 967, 285-9. 

The study of peptidergic neurons requires a number of special tools 328... 

The study of peptidergic neurons requires a number of special tools. These tools include methods to detect the neuropeptides both in cells and after release, the enzymes specific to their biosynthesis and their cognate receptors. Since the actions of peptides require secretion, measurements of cell content (e.g. immunostaining) can be deceptive, with a decrease in content reflecting increased release. 

Helke, C. J., Krause, J. E., Mantyh, P. W., Couture, R. and Bannon, M. J. Diversity in mammalian tachykinin peptidergic neurons multiple peptides, receptors, and regulatory mechanisms. FASEB J 4 1606-1615,1990. 

Wotjak CT, Ganster J, Kohl G, Holsboer F, Landgraf R, Engelmann M (1998) Dissociated central and peripheral release of vasopressin, but not oxytocin, in response to repeated swim stress new insights into the secretory capacities of peptidergic neurons. Neuroscience 85 1209-1222... 

Kupfermann, Irving. 1991. "Hypothalamus and Limbic System Peptidergic Neurons, Homeostasis, and Emotional Behavior." In Principles of Neural Science, edited by Eric R- Kandel, James H. Schwartz, and Thomas M. Jessell. 3d ed. New York Elsevier. 

The role of peptidergic neurons is not so clear. Capsaicin, the hot chile pepper chemical that evokes release of peptide transmitters from several types of sensory nerves, has been shown to reproduce some of the signs of bronchial hyperreactivity in animal and human experiments. These findings led to the proposal that sensitization of afferent nerve endings played a major role in chronic airway hyperreactivity. However, peptide transmitter antagonists have not been able to prevent bronchoconstriction in several models. Clearly, much remains to be learned about airway pharmacology. 

An elegant demonstration that the larval/adult transformation, resulting in sexual differentiation, is, in fact, associated with a neurosecretory mechanism has been made by Gustafsson and co-workers (207, 278, 280, 281,283). They showed that a clear activation of the peptidergic neurones took place when plerocercoid larvae of Diphyllobothrium dendriticum were transferred from the poikilothermic intermediate fish host to the final homeothermic bird host. The effect could also be reproduced by cultivating... 

Le Moine C, Bloch B (1996) Expression of the D3 dopamine receptor in peptidergic neurons of the nucleus accumbens comparison with the D1 and D2 dopamine receptors. Neuroscience 73 131-143. 

Lechner J, Leah JD, Zimmerman M (1993) Brainstem peptidergic neurons projecting to the medial and lateral thalamus and zona incerta in the rat. Brain Res 603 47-56. 

A major step forward, which extended our understanding of the range of neuropeptide activities, occurred after the advent of electron microscopy. The observation of synapse-like ("synaptoid") contacts between peptidergic neuron terminals and endocrine cells (in the corpus allatum as well as the adenohypophysis) clearly indicated that close-range signals from neural to endocrine cells contribute to the process of neuroendocrine communication. Subsequently, such peptidergic contacts turned out not to be restricted to endocrine cells they also occur on various somatic cells. 

More importantly, they establish connections between conventional as well as peptidergic neurons. 

At this juncture, a new type of interneuronal communication, i.e., the capacity of neuropeptides to act as neurotransmitters, had become established. Moreover, the structural parameters of peptidergic innervation were seen to include junctional complexes between two peptidergic neurons that seem to enable a reciprocal exchange of signals. 

Gerfen CR, Young WS (1988) Distribution of striatonigral and striatopallidal peptidergic neurons in both patch and matrix compartments an in situ hybridization histochemistry and fluorescent retrograde tracing study. Brain Res., 460, 161-167. 

Finally, NT-3 has recently been shown to increase the levels of several neuropeptides, including somatostatin and substance P, in cortex, hippocampus and striatum of neoanatal rats (Carnahan and Nawa, 1995). If this action persists in adult animals, it may offer the possibility of NT-3 being used in Alzheimer s disease to rescue not only basal forebrain cholinergic neurons but also cortical peptidergic neurons. 

Peptidergic neurons WSP, NKA, DynA Arenas, Akervo, Wong,... 

Eckert, M, and Ude, J. (1983) Immunocytochemical techniques for demonstration of peptidergic neurons, mFunctional Neuroanatomy (Strausfeld, N. J, ed.), Spnnger, Berlin, pp. 267—301... 

McNabb S.L., Baker J.D., Agapite J., SteUer H., Riddiford L.M., and Truman J.H. 1997. Disruption of a behavioural sequence by targeted death of peptidergic neurons in Drosophila. Neuron 4 813-823. 

Hokfelt T, Johansson O, Ljungdahl A et al (1980) Peptidergic neurones. Nature 284 515-521... 

Eckert M, Ude J (1983) Immunocytochemical techniques for the identification of peptidergic neurons. Functional neuroanatomy. Springer, Berlin, pp 268-301... 

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