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T Wessel

Publications and source records attributed to T Wessel.

5 recordsLinked to original sources
PubMed1992

Dopa-decarboxylation in the striata of rats with unilateral substantia nigra lesions.

The source and site of the DOPA decarboxylation to dopamine in Parkinson's disease (PD) and animal models of PD are controversial. Since most of aromatic L-amino acid decarboxylase (AADC) are lost along with the degenerating dopaminergic neurons, we addressed the possibility that other decarboxylases or a novel protein that is structurally different from AADC decarboxylate L-DOPA in the denervated striatum. Immunotitration of the extracts from the denervated striatum with AADC antibody showed that all activity can be attributed to AADC-immunoreactive protein. We then investigated if there are non-dopaminergic intrinsic striatal neurons that express AADC. No evidence of such neurons was noted by immunocytochemistry and in situ hybridization.

Animals↗
PubMed1992

Human urinary trypsin inhibitor (urinastatin)-like substance in mouse liver.

Mouse liver contains a human urinary trypsin inhibitor (urinastatin, UT)-like immunoreactive substance with trypsin inhibitory activity. Northern blot analysis demonstrates the presence of the appropriate 1.3 kb mRNA band in liver tissue but not in kidney or other tissues examined. Administration of hydrocortisone, which is known to increase the urinary excretion of the UT-like substance, increased the levels of UT-like substance in serum and in the liver tissue. In contrast, deoxycorticosterone acetate did not have such an effect. These results suggest that the gene encoding UT-like substance is primarily expressed in the liver of the mouse, and that glucocorticoids play an important role in regulating the hepatic synthesis of UT-like substance. Furthermore, these findings indicate that the mouse is a suitable species for research on the biological function of UT or UT-like substances.

Animals↗
PubMed1991

Characterization of recombinant bovine phenylethanolamine N-methyltransferase expressed in a mouse C127 cell line.

Bovine phenylethanolamine N-methyltransferase (PNMT) cDNA was inserted into a bovine papilloma virus-based expression vector and used to transfect a mouse C127 cell line. The resultant recombinant bovine PNMT was characterized biochemically and immunochemically. Recombinant bovine PNMT activity, like the native bovine enzyme, was enhanced by phosphate ion in a concentration-dependent manner. Their molecular weights were shown to be identical by Western blot analysis. Antibodies raised against native bovine adrenal PNMT equally immunoprecipitated the activity of the recombinant and native enzymes. In addition, double immunodiffusion analysis showed a single precipitin line of confluence with both enzyme preparations, indicating immunological identity of native and recombinant bovine PNMT. These antibodies immunostained the recombinant enzyme protein in transfected cells and in their neurite-like processes. In addition, in situ hybridization with the bovine PNMT cDNA probe resulted in a labelling pattern similar to the immunostaining. The recombinant bovine PNMT as the native bovine enzyme exist in multiple-charge forms, but only one form is predominant. Taken together, our results suggest that recombinant bovine PNMT, expressed from bovine PNMT cDNA in a mouse cell line is enzymatically active and shares many common features with native bovine adrenal PNMT.

Adrenal Glands↗
PubMed1990

Decrease in tyrosine hydroxylase, but not aromatic L-amino acid decarboxylase, messenger RNA in rat olfactory bulb following neonatal, unilateral odor deprivation.

Unilateral naris cauterization in rats results in occlusion of the affected naris and blockade of odorant access to ipsilateral olfactory receptor cells in the olfactory epithelium. These receptor cells project exclusively to the olfactory bulb (OB) and appear to regulate expression of the dopaminergic phenotype in a population of OB juxtaglomerular neurons. Unilateral odor deprivation results in a loss of normal stimulatory input to the OB and a marked and specific decrease in ipsilateral OB tyrosine hydroxylase (TH) expression. The expression of co-localized aromatic L-amino acid decarboxylase (AADC) is not similarly affected. We have used this procedure in neonatal rats to examine the effect of stimulus deprivation on OB TH and AADC mRNA levels. Both Northern blot and in situ hybridization analyses revealed a pronounced decrease in ipsilateral as compared to contralateral OB TH mRNA levels 40 days after naris closure. In contrast, the levels of OB AADC mRNA were unaltered by naris closure. By in situ hybridization histochemistry, both TH and AADC mRNAs were localized to OB juxtaglomerular neurons. Odor deprivation was associated with an apparent region-specific reduction in TH mRNA within the ipsilateral OB glomerular layer. By densitometric analysis, the loss of TH-specific message was quantitatively consistent with the decrease in TH activity, suggesting that the observed plasticity of OB dopaminergic neurons following functional deafferentation can be attributed to a selective, transneuronally-mediated down regulation of TH gene transcription.

Animals↗