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1. A study of the effect of changes in the hepatic portal venous pressure (HPVP) on the rate of urine flow in dogs has been made. Normally this pressure varies between 3·7 and 14·9 cm H2O. It can be raised or lowered by varying the method of manipulation of the visceral organs. 2. When the HPVP was raised within 15 cm H2O above the premanipulation level it caused an increase in urine flow to 2-3 times the normal levels within 2-5 sec. If the HPVP was raised to more than 15 cm H2O above the pre-manipulation levels it resulted in a period of antidiuresis. The urine flow returned rapidly to normal level immediately after the pressure was released. 3. The kidney volume increased when an induced diuresis occurred and decreased when an antidiuresis occurred. 4. The urine chloride concentration decreased during diuresis, but total chloride excretion increased. Total chloride excretion was reduced when an antidiuresis occurred. 5. Topical application of local anaesthetics at the hilus of the kidney and on the renal nervous plexus abolished the response. This and other evidence indicate that this effect on urine flow is a result of nervous reflex activity, probably involving the sympathetic but not the vagus. 6. The receptive area lies in the mesentery between the mesenteric capillaries and the main portal vein.

1. Adrenaline or noradrenaline in single doses (0·01–0·10 μg/kg) or by continuous infusion (0·3–3·0 μg.kg−1 min−1) into anaesthetized dogs has been administered by different routes. The changes in femoral arterial B.P., hepatic portal venous pressure, renal venous pressure, intrarenal venous pressure, kidney volume, renal plasma flow (RPF), glomerular filtration rate, urine flow and plasma protein concentration have been followed. The effects varied with route of administration, with dose and time. 2. Direct injection of single doses of these drugs (≤ 0·02 μg/kg) into the renal artery reduced RPF and urine flow without affecting the systemic B.P. or hepatic portal venous pressure. 3. When the catecholamines were administered in single small doses (≤ 0·02 μg/kg), I.M. or S.C. or via the hepatic or common carotid arteries, only a slight effect on systemic B.P. was observed. There was little effect on hepatic portal venous pressure, and no diuresis was observed. 4. Single injection of these drugs (≤ 0·02 μg/kg) into the mesenteric artery caused an immediate fall of hepatic portal venous pressure without a direct effect on the kidney. A subsequent rise in hepatic portal venous pressure was associated with an increase in urine flow. 5. Administration of these drugs (0·01–0·10 μg/kg) into the femoral vein, inferior vena cava or internal jugular vein caused a great rise in systemic B.P., a decrease in hepatic portal venous pressure and an antidiuresis, but this was usually followed by a rise of hepatic portal venous pressure and by an associated diuresis, as systemic B.P. returned to normal values. 6. The total and segmental renal vascular resistance were calculated from parameters measured during ureteral occlusion. The primary effect of the catecholamines was to increase the resistance in all renal vascular segments and produce antidiuresis; subsequently a drastic drop of all segmental resistances occurred and this was accompanied by a diuresis. 7. After block of the α-adrenergic receptors by dibenzyline or ergotamine, manipulations which increased the hepatic portal venous pressure could still evoke an immediate reflex diuresis. 8. Since the primary renal effect of catecholamines is a vasoconstriction and antidiuresis, it seems that the subsequent reduction of the renal vascular resistance and the associated diuresis is caused by some other mechanism. 9. It is concluded that the complex effects of catecholamine on renal function represent the resultant of direct intrarenal together with indirect extrarenal actions and that the relative significance of these various actions depends on dose, time and the route of administration.

Der Einflus hoher Konzentrationen von AlF 3 auf die Ionenleitfahigkeit von PbF2 und seine Kristallstruktur wird im Temperaturbereich zwischen -5O und 300°C untersucht.