Specificity in the enzymic conversion of polyunsaturated fatty acids into prostaglandins

Abstract

The enzyme specificity in the biosynthesis of prostaglandins has been investigated by incubation of a particulate fraction of sheep vesicular glands with w6 tri-and tetraenoic CIS-CZZ fatty acids and isomers of w6 eicosatrienoic acid (20 : 3 06). The chemical synthesis of the various substrate fatty acids is described. The tetraenoic fatty acids were converted into a series of prostaglandin Ez homologues and the trienoic fatty acids into a series of prostaglandin El homologues. The only isomer of 20 : 3 w6 which showed a fairly high conversion into an isoprostaglandin E l was the 0 7 compound. Maximum conversions were obtained from w6 CZO acids.The smooth muscle stimulating activity of prostaglandin EL and Ez appears to be very specific. All other prostaglandins had much lower activities.

A Metal-Free Oxygenated Covalent Triazine 2-D Photocatalyst Works Effectively from the Ultraviolet to Near-Infrared Spectrum for Water Oxidation Apart from Water Reduction

“…Figure 2 b shows further structural characterization from DRIFT, which clearly confirmed the existence of triazine units and C=O bonds in the OCT in the following details. The peaks at 1017 and 808 cm –1 match well with the C=C bending of benzene units 35 , 36 and the C–H in-plane bending vibrations of the benzene rings, 36 respectively. The characteristic bonds for the triazine unit were found at 1537 cm –1 (C–N stretching mode) 31 , 37 and 1358 cm –1 (in-plane ring stretching vibrations), 37 , 38 confirming the successful formation of triazine rings in our experiments.…”

Chemical Synthesis and Gas Chromatographic Behaviour of γ‐Stearidonic (18:4n‐6) Acid

“…A full chemical synthesis of this fatty acid was described [5]. When used in the early studies of prostaglandin biosynthesis, this fatty acid proved to be an approximately 6.5 times poorer substrate than 20:4n-6, as judged by the yield of prostaglandins (determined by absorbance at 278 nm after alkali treatment) after 30 min incubation of fatty acids with the particulate enzyme fraction of sheep vesicular glands [6]. Whilst the publication describing the synthesis of 18:4n-6 is occasionally cited, it is usually because of another synthesis described in the same paper, namely that of 20:4n-6.…”

Influence of dietary fat, meal pattern and length of feeding on cholesterol metabolism, cardiac stress-strain response and morphology in maturing male rats

“…On the other hand, the influence of polyunsaturated fatty acids (PUFA) on elastin and collagen seemed to be more subtle. Their action has been associated with that of prostaglandins (PG) (Struyk et al, 1966;Vergroesen, 1972). Coronary flow was stimulated by PGFi and PGF2, while with certain cation ratios (K-Ca) PCFi^ and PGF2a could stimulate the contractile force in isolated frog and rat heart (Vergroesen and De Boer, 1968).…”