The diuretic actions of prostaglandin E1 and of noradrenaline, and the occurrence of a prostaglandin E1-like substance in the renal lymph of cats

1. The actions of noradrenaline, prostaglandin E(1) and angiotensin II-amide on various parameters of renal function and on the flow of renal lymph and its equivalent content of prostaglandin E(1)-like activity have been compared in cats under chloralose anaesthesia.2. All three compounds produced diuresis and natriuresis. Noradrenaline (0.1-0.3 mug/kg.min) and angiotensin II (0.1-0.2 mug/kg.min) with rise of the filtration fraction (FF) and GFR; prostaglandin E(1) (0.13-0.19mug kg.min) with increase in GFR but without change in FF. Noradrenaline and angiotensin markedly raised renal perfusion pressure, prostaglandin E(1) lowered it by approximately 10 mm Hg.3. All three compounds increased the renal lymph flow. Only PGE(1) and noradrenaline markedly raised the equivalent concentration of PGE(1) in the renal lymph.4. Complete block of alpha and beta adrenergic receptors prevented the vasopressor effect and the rise in FF caused by noradrenaline but did not markedly reduce the diuretic and natriuretic effects nor the influence on renal lymph.5. Effects of PGE(1) and of angiotensin were unaffected by alpha and beta adrenergic block and atropinization did not prevent the release of PGE(1)-like material or the diuresis caused by noradrenaline.6. It is suggested that the diuretic and natriutetic actions of noradrenaline are in large part attributable to the intrarenal action of this PGE(1)-like substance of unknown origin.

Monoamine oxidase activities in tissues of thiamine-deficient rats

The oxidation of monoamine by homogenates of tissues of thiamine-deficient rats was measured with noradrenaline as substrate. Monoamine oxidase activities were depressed in tissues in which the catecholamine content had previously been found raised during thiamine deficiency, with the exception in the cerebral cortex. The impaired enzyme activities were restored to the control level by repeated thiamine injections. An accumulation of pyruvic acid did not inhibit monoamine oxidase activity and thiamine pyrophosphate is not implicated as a co-factor in the oxidation of monoamine substrate.

Basic studies on the viability of El Tor vibrios

Quantitative data are presented on the viability of El Tor vibrios in various foodstuffs under different conditions. El Tor vibrios were found to have a very short life in water at -20 degrees C, but in various nutrient media, such as skim milk, sugar solution or meat extract, they could live for more than a month at this temperature; the survival rate was always much higher when the vibrio suspension was cooled rapidly to -72 degrees C and stored at this temperature.The optimum pH for the growth and survival of El Tor vibrios is 6-8, and the optimum osmotic pressure 250 mOsm-700 mOsm. The resistance of El Tor vibrios to disinfectants is lower than that of salmonellae and Escherichia coli. The El Tor vibrios are more resistant than classical cholera vibrios to such disinfectants as benzethonium chloride and o-dichlorobenzene. They are not resistant to sodium hypochlorite or bleaching powder at 6 ppm.The results of the investigation emphasize the necessity of immediate and proper disinfection of foodstuffs contaminated with El Tor vibrios, and indicate the possibility of survival of the organisms for long periods under favourable conditions.

Chemical degradation of dipicolinic acid-C14 and its application in biosynthesis by Penicillium citreo-viride

Kanie, Matuso (Kagoshima University, Kagoshima, Japan), Shigeo Fujimoto, and J. W. Foster. Chemical degradation of dipicolinic acid-C(14) and its application to biosynthesis by Penicillium citreo-viride. J. Bacteriol. 91:570-577. 1966.-A chemical degradation of dipicolinic acid-C(14) has been worked out, enabling determination of the specific radioactivity of the carboxyl-carbons (carbons-7 and -8), and of the following carbons of the pyridine ring: carbons-2 and -6 combined, carbons-3 and -5 combined, and carbon-4. The degradation was applied to dipicolinic acid synthesized by washed, submerged mycelium of the mold from glucose and C(14)O(2), and from glucose-1-C(14), -2-C(14), and -6-C(14). The distribution of radioactivity within the labeled dipicolinic acids is consistent with operation of respiratory cycles and with the incorporation of one molecule of CO(2) in the pyridine acid. A C(3) compound is a primary building block. The C(7) chain is believed to result from a C(3) plus C(4) condensation, pyruvic acid and aspartic acid beta-semialdehyde being proposed as likely precursors. Other aspects of the biosynthesis of C(7) open-chain compounds and of dipicolinic acid are discussed.