Dopamine Sulphotransferase Is Better Developed than p-Nitrophenol Sulphotransferase in the Human Fetus

Abstract

The distribution patterns of two forms of sulphotransferase were studied in human adult and fetal tissues. One form was studied with p-nitrophenol as substrate and it is referred to as ‘TS’. The other form was studied with dopamine as substrate and it is referred to as ‘TL’. The activities of TS (pmol × min^-1 × mg^-1; mean ± SD) were 1,077 ± 293 (adult liver; n = 6), 97.8 ± 26.4 (fetal liver; n = 8); 38.0 ± 12.8 (adult kidney; n = 5), 28.5 ± 21.5 (fetal kidney; n = 8); 78.9 ± 21.3 (adult lung, ex-smokers; n = 5), 83.0 ± 23.1 (adult lung, smokers; n= 5), 25.8 ± 10.0 (fetal lung; n = 8), 140.8 ± 18.9 (ileum; n = 5), 68.6 ± 30.7 (ascending colon; n = 5), 28.6 ± 10.8 (fetal gut; n = 8), 23.9 ± 14.5 (placenta; n = 5). The adult to fetal ratios for TS were 11.0 (liver), 1.3 (kidney), 3.1 (lung) and 2.6 (gut). The activities of TL were 28.9 ± 17.4 (adult liver; n = 6), 97.2 ± 52.3 (fetal liver; n = 8); 10.3 ± 4.7 (adult kidney; n = 5), 37.7 ± 29.9 (fetal kidney; n = 8); 79.6 ± 18.8 (adult lung, exsmokers; n = 5), 76.3 ± 23.7 (adult lung, smokers; n = 5), 98.2 ± 55.0 (fetal lung; n = 8); 391.2 ± 37.3 (ileum; n = 5), 161.5 ± 66.0 (ascending colon; n = 5), 200.6 ± 137.1 (fetal gut; n = 8), 21.8 ± 13.6 (placenta; n = 5). The adult to fetal ratios for TL were 0.3 (liver), 0.3 (kidney), 0.8 (lung) and 0.8 (gut). TL is better developed than TS in the human fetus. These data also show that TS and TL are more active in ileum than colon mucosa of adult subjects. Smoking does not affect the enzymes in the lung.

Human liver budesonide sulphotransferase is inhibited by testosterone and correlates with by testosterone sulphotransferase

“…Lack of metabolism of budesonide has been described in human tung preparations (Andersson and Ryrfeldt 1984), whereas sulphotransferase has been detected in this tissue (Cappiello et al 1991;Pacifici et al 1988 a,b). The sulphation of budesonide in the lung should limit its systemic bioavailability, so we extended the investigation to the human lung.…”

“…Phenol and catechol sulphotransferases were measured using p-nitrophenol and dopamine as substrates as described by Foldes and Meek (1973), modified by Anderson and Weinshilboum (1980) and adapted to human tissues by Cappiello et al (1990Cappiello et al ( , 1991. …”

Uridine 5′ — Diphosphoglucuronic acid (UDPGLcUA) in the human fetal liver, kidney and placenta

“…This picture is corroborated by the comparison of the concentrations of the endogenous substrates of UDPglucuronosyltransferase, UDPGLcUA, and of suplhotransferase, adenosine -3' -phosphate 5' -phosphosulphate (pAPS; 13), in the human fetal and adult tissues. The fetal liver concentration of PAPS is about half ot that in the adult liver (13) whereas the concentration of UDPGLcUA is only one fifth. These results indicate the inadequacy of fetal glucuronidation and are in accord with the view than sulphation is better developed than glucuronidation in the human fetus.…”

“…UDP-glucuronosyltransferase and sulphotransferase share many substrates but the ontogenic development of these enzymes is different. Sulphotransferase develops early in gestation (2,13,14) in contrast to UDP - g1ucuronosyItransferase which develops late in gestation and predominates in post-gestation life (2,7,8,15). This picture is corroborated by the comparison of the concentrations of the endogenous substrates of UDPglucuronosyltransferase, UDPGLcUA, and of suplhotransferase, adenosine -3' -phosphate 5' -phosphosulphate (pAPS; 13), in the human fetal and adult tissues.…”

Genetic variation, expression and ontogeny of sulfotransferase SULT2A1 in humans

“…[1][2][3][4] Other substrates such as dopamine and ritodrine are mainly catalyzed by SULT1A3/A4 (also known as M-PST) which also appears to have a higher sulfonation rate in the human fetal than adult livers. 5,28 However, the opposite has also been described for the activity of SULT1A2 (P-PST) which was found to be higher in adults than in the fetal livers. 28 For obvious reasons a limitation with our study is the small amount of tissue specimens available from the fetuses in the age range studied.…”