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C J Dalsgaard

Publications and source records attributed to C J Dalsgaard.

79 records · Page 5Linked to original sources
PubMed1982

Substance P-containing primary sensory neurons projecting to the inferior mesenteric ganglion: evidence from combined retrograde tracing and immunohistochemistry.

The origin of substance P-containing fibres in the inferior mesenteric ganglion of the guinea-pig was studied by combining retrograde tracing and indirect immunofluorescence techniques. 'True Blue' or propidium iodide was injected into the inferior mesenteric ganglion. Four days later the animals were perfused with formalin and the dorsal root ganglia L2 and L3 were dissected out. Sections of the spinal ganglia were cut on a cryostat and analysed in a fluorescence microscope with appropriate filter combinations and subsequently processed for indirect immunofluorescence using antiserum to substance P. Several ganglion cells containing both dye (True Blue or propidium iodide) and substance P-like immunoreactivity were observed, strongly supporting the view that at least some of the substance P fibres in the inferior mesenteric ganglion are of sensory nature. Taken together with physiological results from other workers, the present findings suggest that substance P can be released from peripheral, sensory nerve endings, inducing changes in the membrane potential of sympathetic neurons.

Animals↗
PubMed1982

Enkephalin-containing sympathetic preganglionic neurons projecting to the inferior mesenteric ganglion: evidence from combined retrograde tracing and immunohistochemistry.

The origin of fibers containing enkephalin immunoreactivity in the inferior mesenteric ganglion of the guinea-pig was studied by combining retrograde axonal tracing and indirect immunofluorescence techniques. Fast Blue was applied into the inferior mesenteric ganglion. Three days later colchicine was administered into the subarachnoid space in order to increase the peptide content of the spinal cord cell bodies. The drug was injected through a catheter which was inserted into the cisterna magna and moved to the appropriate spinal cord levels. After the colchicine injection the animals were perfused with formalin and the L2-L3 spinal cord segments were dissected. Cryostat sections of the spinal cord were analyzed in a fluorescence microscope and subsequently processed for indirect immunohistochemistry using antiserum against enkephalin. Several sympathetic preganglionic neurons containing both Fast Blue and enkephalin-like immunoreactivity were seem mainly in the intermediolateral cell column of the cord. The observations strongly support the view that at least some of the enkephalin-containing fibers in the inferior mesenteric ganglion originate in the sympathetic preganglionic nuclei of the spinal cord. These findings are discussed in view of recent physiological studies which have shown that enkephalin may have a presynaptic inhibitory action on preganglionic neurons as well as on substance P containing primary afferent neurons in the inferior mesenteric ganglion.

Adrenergic Fibers↗
PubMed1981

The distribution of the sympathetic preganglionic neurons projecting onto the stellate ganglion of the guinea pig. A horseradish peroxidase study.

After injection of horseradish peroxidase (HRP) into the stellate ganglion (SG) of the guinea pig, labelled cells were found in the C8-T11 spinal cord segments. The HRP-positive neurons were located in the nucleus intermedio-lateralis pars principalis and funicularis (ILp and ILf) and in the nucleus intercalatus proprius and pars paraependymalis (ICp and ICpe). The ICp and ICpe neurons represented approximately one-fourth of the total number of labelled cells. The ILp and ILf neurons were mainly located in the T2 and T3 segments whereas the ICp and ICpe neurons occurred mainly in the T4 to T6 segments where the ICpe cell group formed a continuous cell column dorsal to the central canal. The possible correlation between the segmental distribution and peripheral sympathetic effects was discussed.

Adrenergic Fibers↗
PubMedDate not supplied

Stimulation of connective tissue cell growth by substance P and substance K.

Connective tissue cells proliferate actively when cultured in the presence of serum. Platelet-derived growth factor (PDGF), a basic protein of relative molecular mass approximately 30,000, has been identified as the major serum mitogen for these cells; its main physiological/pathophysiological role may be to initiate wound healing in connection with tissue injury. However, growth of cultured cells is also influenced by several other factors, including epidermal growth factor, fibroblast growth factor, insulin and somatomedins. Furthermore, Rozengurt and Sinnett-Smith recently showed that bombesin, a neuroendocrine peptide isolated from frog skin, stimulates DNA synthesis and cell division in cultures of a specific subtype of 3T3 cells. Substance P and substance K (also known as neurokinin A or neuromedin L) are mammalian peptides belonging to the tachykinin family. Substance P has been studied extensively; it is distributed widely throughout the central and peripheral nervous system, including primary sensory neurones, and can be released in the periphery from axon collaterals of stimulated pain fibres and contribute to the inflammatory response. Substance K is a member of the tachykinin family isolated from mammalian spinal cord; Nawa et al. determined the primary structure of two types of substance P precursors, one of which contained a sequence homologous to substance K, as well as the sequence of substance P. We report here that substance P and substance K stimulate DNA synthesis in cultured arterial smooth muscle cells and human skin fibroblasts, and that this stimulation is inhibited by the substance P-antagonist spantide.

Animals↗