Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:1.6.99.3 (diaphorase)
 5,903 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Serotoninergic and cholinergic neurons are known to appear earlier in the ontogeny (day E12) of the murine gut than those containing substance P or vasoactive intestinal peptide (day E14). It has also been demonstrated that proliferating neural precursors coexist with mature neurons in developing enteric ganglia. These observations have led to the hypotheses that peptidergic neurons develop later than those that utilize small molecule neurotransmitters and that the activity of early developing neurons may affect the phenotypic expression of coexisting neuroblasts. As a partial test of these hypotheses we studied the phenotypic expression of neurons recognized by antisera to neuropeptide Y (NPY) and calcitonin gene-related peptide (CGRP), and of those visualized by the histochemical demonstration of reduced nicotinamide adenine dinucleotide phosphate (NADPH) diaphorase activity. NADPH diaphorase activity, which is coexpressed with NPY immunoreactivity in all submucosal and many myenteric neurons, was first found on day E11 in clusters of cells in the dorsal mesogastrium. These cells also expressed neurofilament reactivity and thus were developing along a neuronal lineage. Enteric neurons that expressed NADPH diaphorase activity were visualized in the stomach one day later, on day E12. At this time, NADPH diaphorase-containing cells could no longer be demonstrated in the dorsal mesogastrium. NPY immunoreactivity first appeared in the wall of the bowel on day E12, when it was seen in cells in the presumptive stomach. By day E13, the entire length of the bowel contained NPY-immunoreactive neurons. Cells that displayed NADPH diaphorase activity were found at this time at both ends of the alimentary tract, but did not appear in the ileum until day E18. In contrast, CGRP immunoreactivity could not be detected anywhere in the gut until day E17, but by day E18 all regions of the bowel contained CGRP-immunoreactive neurons. Endogenous 5-HT was first detected at day E16 in mucosal epithelial cells in all segments of the gut except the stomach, where it appeared at day E18. The NPY/NADPH diaphorase set of neurons thus develop before the acquisition of a detectable level of endogenous 5-HT or enteric neural 5-HT receptors (which arise in the foregut at day E14). These observations demonstrate that enteric neurons that express small molecule neurotransmitters do not necessarily develop earlier than peptidergic neurons as a class; however, various types of enteric neurons do appear in a sequential order.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Time course of expression of neuropeptide Y, calcitonin gene-related peptide, and NADPH diaphorase activity in neurons of the developing murine bowel and the appearance of 5-hydroxytryptamine in mucosal enterochromaffin cells. 278 79

Nicotine adenine dinucleotide phosphate-diaphorase staining was used to study nitric oxide synthase activity and distribution in the midbrain visual structures of white leghorn chick embryos and post-hatched chickens. Enzyme staining first appeared in the isthmic region at the tenth embryonic day (E10) in the neuropil of the nucleus isthmi, pars parvocellularis. At E11 faint enzyme positivity appeared also in the nucl. isthmi pars magnocellularis, the nucl. semilunaris and the nucl. isthmo-opticus. The staining intensity of the isthmic nuclei dramatically increased between the 12.5th and the 13th days of incubation. The nucl. isthmi, pars parvocellularis showed the strongest enzyme reaction throughout embryonic life. A day before hatching all the isthmic nuclei were heavily stained, however, nicotine adenine dinucleotide phosphate-diaphorase-positive cells occurred exclusively in the nucleus isthmo-opticus. In the tectum opticum, intensely stained cells occupied the stratum fibrosum et griseum superficiale. The layer containing the projection neurons to the isthmo-optic nucleus was unstained. In the isthmic region, the intensity of staining surpassed that of the tectum and reached its maximum at E17 and then slowly decreased till the end of the experimental period (120 days post-hatched). The tractus isthmo-opticus showed nicotine adenine dinucleotide phosphate-diaphorase activity throughout the investigated period of life of the chicken, but the tractus tectoisthmo-opticus was unstained. Our results suggest that in the isthmic nuclei, nicotine adenine dinucleotide phosphate-diaphorase-positive neurons occur only in the isthmo-optic nucleus and optic tectum. The other positively stained structures are the fibers and terminals of tectal cells. In most brain areas nicotine adenine dinucleotide phosphate-diaphorase indicates nitric oxide synthase that produces nitric oxide. The transient appearance of this molecule is probably necessary for neuronal differentiation or the establishment of synaptic connections in the isthmic nuclei, and these developmental changes are under the control of the optic tectum.
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PMID:Developmental changes of NADPH-diaphorase positive structures in the isthmic nuclei of the chick. 1090 5