Renin-angiotensin system responses of acute graded hemorrhage in dogs.

The effect of acute hemorrhage on hemodynamics and the renin-angiotensin system (RAS) was studied in eight anesthetized dogs. Stepwise blood loss to 17 +/- 6.2 ml/kg within 9 to 33 min decreased cardiac output (CO) to 42.8% of control. Mean arterial blood pressure was decreased to 35%, peripheral vascular resistance (PVR) was 1.58-fold increased, plasma renin activity (PRA) and plasma renin concentration (PRC) were increased 3.6-fold and 4.3-fold, respectively, angiotensin I (A I) concentration in plasma was 3.7-fold increased, angiotensin II (A II) was 3.8-fold increased, and A I-degrading enzyme was strongly decreased. Angiotensinogen, A I-converting enzyme, and A II-degrading enzyme activities into blood circulation were not significantly changed. The minimal blood loss to activate the RAS was 3 ml/kg. The rate of plasma active renin (PRA and PRC) increase depended on the velocity of blood withdrawn. PRA was correlated inversely to CO. PVR correlated linearly to increased plasma angiotensin concentrations. The experiments conducted demonstrate the high sensitivity and prompt activation of RAS to blood loss and suggest that RAS is involved in the regulating mechanisms of hemodynamics during acute graded hemorrhage. The stimulation of RAS supports survival of grave blood loss.

Investigations of components of the renin-angiotensin system in rat vascular tissue.

Investigations were performed on components of the renin-angiotensin system (RAS) in homogenate extracts of vascular tissue and aortic smooth muscle cells cultivated in vitro. Determinations of isoelectric points and pH optima indicated the existence in aortic homogenate extracts of two local angiotensin I (AI)-forming enzymes (AIFE) that were different from those of plasma, renal cortex, veins, and aortic smooth muscle cells. The pH optima for AI-converting enzyme (ACE) from vascular tissues, aortic smooth muscle cells, and plasma were in the same range (pH 8.0-8.5), and in agreement with those measured previously in other tissues. In contrast, in vitro studies with the ACE inhibitors MK-421 and MK-422 and measurement of isoelectric points suggested that aortic ACE was different from the plasma enzyme. AIFE and ACE activities were found to be elevated in spontaneously hypertensive rats (SHR). The biochemical characteristics of the enzymes investigated in the vascular tissue of SHR were not different from those of the normotensive controls. AI- and AII-degrading enzymes were found both in aortic tissue and in aortic smooth muscle cells. One potent AI-degrading enzyme different from ACE was observed in aortic tissue. A high ratio of AI/AII immunoreactivities in arterial walls suggests the availability of renin substrate, and that AI-degrading enzymes are the rate-limiting enzymes for AII formation. The results further support the concept of an intrinsic vascular RAS.

[Clofibrate and phosphate metabolism]. / Clofibrat und Phosphatmetabolismus.

Experiments on rabbits with clofibrate and phosphate added to cholesterol-rich (2%) diet showed similar effects of both substances. During the first month of the experiment, total plasma lipid and total cholesterol level remained within normal range, thereafter up to the third month their level increased. The phosphataemia and phosphaturia showed similar dynamics. The results suggest a similar mechanism of action of both studied substances.

[Micromelia symptomatology and chondrodystrophia calcificans congenita]. / Mikromelie-Symptomatik und Chondrodystrophia calcificans congenita.

The author made a report progress on micromelia symptom on the occasion of a 51 years old patient. It was ascertained that: 146 cm body height with disproportion between trunk and extremities, marked small hands and feet, with positional anomaly of the fingers (clinodaktylia) and toes; calcifications in intraarticular and paraarticular regions particularly in articulation metacarpo- and metatarso-phalangeae; adiposis. The case is interpreted as chondrodystrophia calcificans congenita. The persistent micromelia symptom probable is influenced through additional factor as chondrocalcinosis. Several conceptions on this symptom have been taken into consideration.

The free fatty acid pattern in blood serum in young spontaneously hypertensive rats.

An investigation on the free fatty acid (FFA) profile in blood serum, using liquid gas chromatography, has been carried out on young (8-9 week-old) spontaneously hypertensive rats (SHR). A significative increase in the level of unsaturated FFA was found in SHR in comparison to their controls. The deviations in the composition of the FFA spectrum found were elevation of the polyunsaturated fatty acids: hexadecanoic acid (C16:2), linoleic acid (C18:2), linolenic acid (C18:3), eicosadienoic acid (C20:2), eicosatrienoic acid (C20:3), eicosapentaenoic acid (C20:5). The differences between FFA profile in SHR and control group can reflect genetically controlled variables.

[Multiple lipomatosis and Recklinghausen's neurofibromatosis (author's transl)]. / Multiple Lipomatose und v. Recklinghausensche Neurofibromatose

On the occasion of two separate observations of multiple lipomatosis on a 48 years old female patient and a neurofibromatosis on a 49 years old male patient, the differential diagnosis of these diseases was compiled with regard to the cutaneous and subcutaneous symptoms and to the relations to the nervous system and the inner organs. The differential diagnostical plan requires a series of clinical examinations for the clarification of these pathological conditions, which often comprise more than one disease or one syndrome.

[Effect of angiotensin II on the pattern of plasma free fatty acids in 2 hypertension models in rabbits]. / Der Einfluss von Angiotensin II auf das Muster der freien Fettsäuren im Blutplasma bei zwei verschiedenen Hypertoniemodellen am Kaninchen

The effect of exogenous angiotensin II on the spectrum of nonesterified fatty acids (NEFA) in blood plasma was studied by gas-chromatographic analysis in 10 normotonic rabbits, 12 rabbits with experimental hypertension induced by sinoaortic denervation, and in 14 rabbits with experimental renal hypertension. One minute after injection of angiotensin II, the following changes were found in the spectrum of NEFA: increase in the fraction of saturated, and decrease in the fraction of unsaturated NEFA;the intensity of these changes was higher in the animals with renal hypertension than in those with hypertension induced by sinoaortic denervation, and lowest in the normotonic rabbits. Thirty to sixty minutes after injection the above changes further gained in intensity in both models of hypertension, whereas in normotonic rabbits the changes rather receded. A growing dominance of palmitic acid, persistent elevation of stearic acid, decreases in the levels of monoenolic oleic and palmitoleic acids as well as of polyenolic fatty acids were observed.