Ten hypertensive patients due to renal arterial stenosis were studied to determine the relationship between results of surgical revascularization and bilateral renal biopsy findings.
Seven patients including 5 with no intrarenal vascular lesion and 2 with slight arteriosclerosis, normal blood pressure was achieved after operation except in a case in whom surgery failed to repair his renal ischemia.
In 3 patients showing moderate to severe intrarenal small vessel disease, diastolic blood pressure was lowered to below 90mm. Hg, although one of them needed sometimes small doses of a hypotensive drug postoperatively.
On the basis of the present results, it is postulated that patients of renovascular hypertension even with intrarenal vascular changes, should be treated by surgical reconstruction of the stenotic renal artery whenever the procedure is adequately feasible.

View full abstract

In an attempt to clarify the selective vasoconstriction of different vascularbeds, vasoconstrictor responses of kidney, intestine and lower extremity to the electrical stimulation of the points within the mesencephalon were systematically explored. Three vascular circuits were perfused at constant flow, and changes in vascular resistance were indicated by changes in perfusion pressure. Various points were stimulated by moving electrode position, and systemic arterial pressure and perfusion pressure from 2 of these vascular circuits were simultaneously measured. Central stimulation caused systemic pressor and vasoconstrictor responses of varied degree in 3 vascular circuits. Slight shift in electrode position altered the vasoconstrictor response patterns in these vascular circuits. The points giving maximum systemic pressor and maximum vasoconstrictor responses in kidney, intestine and lower extremity were anatomically separate, though these points were located very closely each other. No anatomical separation was found in control group, both sides of renal or femoral circuits.

View full abstract

(1) The main purpose of this communication is to introduce a newly devised experimental technique for studying electrocardiography and vectorcardiography: a canine heart perfused by means of Langendorff's technique was placed within a transparent plastic molded human torso model filled with Tyrode solution at the physiological temperature of 36°C, the heart was kept beating regularly by the sinus rhythm for more than 2 hours, and it was succeeded in obtaining recordings of the electrical activity of the heart by Frank lead system and by the conventional electrocardiographic leads.
(2) This method contains advantages inherent in both the simplified physical model experiment and the in situ experiment without including disadvantages ascribed to each of the 2 experimental approaches. It can be expected that this method be adopted in many aspects of electrophysiological investigation of the heart.
(3) As an application of this technique, relationship between rotation angle of the suspended canine heart and changes in QRS pattern of electrocardiogram and vectorcardiogram were investigated.

View full abstract

The uneven topographical distribution of blood flow in the lung is an inevitable consequence of the intimate apposition of blood and air which results in large pressure differences across the pulmonary vessels at different levels in the lung. The resulting imbalance of blood flow and ventilation causes large regional differences in gas exchange but interference with overall gas transfer is negligible unless the normal pulmonary arterial pressure is reduced or alveolar pressure is increased when an alveolar dead space may develop. The uneven distribution of blood flow results in peculiar overall pressure-blood flow relations in that the pulmonary vascular resistance falls considerably when either the pulmonary arterial or venous pressures are raised. These characteristics are advantageous to the lung, the one organ of the body which receives the whole cardiac output during a variety of physiological states.
In general, the patterns of distribution of blood flow observed in health and disease can apparently be explained by the interactions between the pulmonary arterial, venous and alveolar pressures. However patients with an increased pulmonary venous pressure as in mitral stenosis or left ventricular failure may show a reduction of blood flow in the lower zones and a similar pattern has been found in the isolated lung where it is caused by interstitial oedema. The mechanism is postulated to be an interference with the normal expanding action of the inflated lung parenchyma on the extra-alveolar blood vessels.

View full abstract