Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.11.1.7 (peroxidase)
 65,474 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Methimazole has been reported to produce extensive degenerative changes in olfactory epithelium and a severe deficit in odor detection [Genter BM, Owens DM, Carlone HB, Crofton KM. Fundam. Appl. Toxicol. 1996;29:71-77; Genter BM, Owens DM, Deamer NJ, Blake BL, Wesley DS, Levi PE. Toxicol. Pathol. 1995;23:477-486.]. To examine this further, rats were tested on olfactory detection and discrimination problems before and after intraperitoneal injection of 300 mg/kg methimazole. In the first 2 days after treatment, experimental rats had nasal congestion and a modest decrement on odor detection and odor mixture discrimination tasks. They performed almost as well as control rats on the third post injection day. In a separate group of rats, anterograde transport of horseradish peroxidase from olfactory epithelium to the bulb was examined 1, 2, 3, and 5 days after administration of methimazole. The treatment produced a modest but progressive disruption of bulbar input: 2 days after administration only approximately 10% of bulbar glomeruli had reduced levels of reaction product while 30-40% of glomeruli had little or no reaction product in 3-5 day survival rats. These results indicate that methimazole is not a particularly effective olfactotoxin and does not produce anosmia or even a severe hyposmia.
 ...
PMID:Olfaction and peripheral olfactory connections in methimazole-treated rats. 1040 14

Transport of wheat germ agglutinin-horseradish peroxidase (WGA-HRP) from olfactory sensory neurons to the olfactory bulb as well as odor detection and discrimination were examined in rats in which each nasal epithelium had been irrigated with 0.1-0.5 ml 5% zinc sulfate. After treatment, rats showed few or no deficits in discriminating among odors and in detecting high (1%-0.01%) concentrations of ethyl acetate, but some had deficits in detecting lower concentrations of the odor. In most cases, HRP reaction product filled more than 30% of olfactory bulb glomeruli 2-4 days after treatment with ZnSO4. The behavioral outcomes are in agreement with recent reports of considerable savings in olfaction even after severe reduction of afferent projections to the olfactory bulb. We conclude that, in the rat, intranasal application of ZnSO4, as generally practiced, does not produce anosmia.
 ...
PMID:Does intranasal application of zinc sulfate produce anosmia in the rat? 1095 40

Here we examine hypothesis that short-term peripheral ZnSO(4)-induced anosmia can produce effects on c-fos expression within spinal cord and caudal medulla in male Wistar rats (n=4). Fos-like-immunoreactive cells revealed by avidin-biotin-peroxidase method show a significant bilateral increase in the nucleus proprius (layers 3 and 4) and medial part of layers 5 and 6. In substantia gelatinosa (layer 2(i)) and area 10 Fos-positive neurons were intermixed together with nicotin-amide adenine dineucleotide phosphate-diaphorase (NADPH-d)-reactive cells. Short-term anosmia enhanced c-fos expression in ventral horn (layers 7 and 8), ventrolateral segment and dorsal part of the spinal trigeminal nuclei. In anosmic rats varicose fibres and numerous NADPH-d-stained neurons were present in the gelatinous layer of the spinal trigeminal nucleus caudalis, and a separate population of Fos-positive cells was detected within this layer. Nucleus tractus solitaris also contained a few NADPH-d-reactive, medium sized neurons intermixed with Fos-immunoreactive cells.
 ...
PMID:Persistent c-fos expression and NADPH-d reactivity in the medulla and the lumbar spinal cord in rat with short-term peripheral anosmia. 1124 40

Mice pre-trained in an olfactometer were tested daily on odor detection and discrimination tasks after irrigation of their olfactory epithelium in each naris with 50 microl of 5% zinc sulfate or saline. Anterograde transport of a wheatgerm agglutinin-horseradish peroxidase (WGA-HRP) conjugate from the epithelium to the olfactory bulb was used to assess anatomical connectivity in these and in mice that were used only for histological analyses. One day after treatment, saline controls performed at high levels of accuracy in detecting vapor from solutions of 5-0.01% ethyl acetate and in an odor discrimination task but most ZnSO4-treated mice performed at chance for 5-30 days before showing recovery. Although dense WGA-HRP reaction product was found in the accessory olfactory bulb, there was little or no evidence for axonal transport to glomeruli of the main olfactory bulb in the first 4-8 days after treatment. These results demonstrate that intranasal application of ZnSO4 to mice produces a brief but essentially total disruption of functional connections from the olfactory epithelium to the main olfactory bulb and a corresponding transient anosmia.
 ...
PMID:Does intranasal application of zinc sulfate produce anosmia in the mouse? An olfactometric and anatomical study. 1462 34