Peritz Scheinberg

Effects of vigorous physical exercise on cerebral circulation and metabolism

Abstract 1.1. The effects of vigorous muscular exercise in the upright posture were studied in thirteen normal subjects and compared with the changes resulting from motionless standing. 2.2. Exercise resulted in a decrease in cerebral vascular resistance and an increase in cerebral oxygen consumption. The decrease in mean cerebral blood flow which results from motionless standing did not occur with exercise. There was no change in cerebral respiratory quotient. 3.3. Although exercise resulted in a striking fall in blood carbon dioxide content and pH, no correlations could be made between these changes and the alterations in cerebral circulatory or metabolic functions. There was a close correlation between changes in cerebral vascular resistance and cerebral oxygen consumption, though the reason for this is not known.

Cerebral blood flow in vascular disease of the brain: With observations on the effects of stellate ganglion block

Abstract 1.1. Values for cerebral blood flow per 100 gm. of brain, arteriovenous oxygen difference, arterio-venous glucose difference, cerebral oxygen utilization, cerebral glucose utilization and cerebrovascular resistance are given in twenty-nine observations on twenty-three patients with cerebral vascular disease. The subjects were either middle aged persons with hypertension and diabetes or patients with a history of a cerebral vascular accident. They were divided into those with normal and those with abnormal mental status. 2.2. Those patients who had no alteration in their mental status had significantly lower cerebral blood flows, higher arteriovenous oxygen differences and higher cerebrovascular resistances than normal young persons. Cerebral oxygen and cerebral glucose utilizations were normal. 3.3. The subjects with abnormal mental status resulting from cerebral vascular disease had significantly lower cerebral blood flows, cerebral oxygen and glucose utilizations and higher cerebrovascular resistances than those with normal mental status or than normal young subjects. 4.4. It is believed that these groups represent two stages in the natural progression of cerebral vascular disease. 5.5. Unilateral stellate ganglion block produced no change in cerebral metabolic functions in normals, patients with hypertensive vascular disease and elderly patients with cerebral thrombosis. The significance of this is discussed. The author is indebted to Dr. Eugene A. Stead, Jr., Department of Medicine, Duke University School of Medicine for much valuable assistance and advice in this study. The work was done with the technical assistance of Mrs. Louise Allen, Miss Dorothy Fredericks and Miss Frances Morgan.

THE EFFECT OF INTRAVENOUS PAPAVERINE HYDROCHLORIDE ON THE CEREBRAL CIRCULATION

Papaverine, one of the benzylisoquinoline derivatives of opium, has found its primary usefulness as a relaxer of the smooth muscle of blood vessels (1). Numerous reports are to be found in the literature as to its effectiveness in the treatment of occlusive and spastic conditions of the pulmonary (2), coronary (3) and peripheral arteries (4-6). In recent years, Russek and Zohman have reported clinical studies in which they felt papaverine had been demonstrated to be an effective therapeutic agent in the treatment of vasospastic conditions involving the cerebral vessels (7). Experimental demonstration of the effect of papaverine hydrochloride on the cerebral vessels has been limited to a report by Shenkin of the effect of 0.06 gm. of the drug intravenously in four patients judged to have decreased cerebral circulation (8). He noted no significant change in cerebral circulatory functions other than a reduction of mean arterial blood pressure and cerebral vascular resistance. The purpose of this paper is to report our findings on the effects of intravenous papaverine on cerebral blood flow and metabolism in 18 subjects, as measured by the nitrous oxide technique (9).

THE EFFECTS OF INTRAVENOUS PRISCOLINE ON CEREBRAL CIRCULATION AND METABOLISM

Priscoline hydrochloride (2-benzyl-imidazolinehydrochloride) is a drug of many pharmacologic actions. The effects of the drug in man apparently depend upon the dosage and method of administration. It is reported to produce peripheral vasodilatation by: 1) adrenergic blockade, inhibiting the effects of circulating adrenalin on smooth muscle cells of blood vessels; 2) sympathetic blockade at the terminations of the sympathetic nerves in the blood vessels; 3) direct action on peripheral vessels; and 4) epinephrine-reversal. There may be sufficient increase in cardiac output to elevate arterial pressure even in the presence of generalized peripheral vasodilatation (1-7). The drug also has other actions not specifically related to the cardiovascular system. Clinically, priscoline has been used widely in the treatment of occlusive and spastic peripheral vascular disease because of its ability to produce an increased cutaneous and muscle blood flow (8-11). Several enthusiastic reports have appeared on the beneficial effects of priscoline on cerebral vessels in the treatment of cerebral vascular disease (1214), and D. Engel has observed dilatation of pial vessels by capillary microscopy through a window in the skull of cats following intravenous priscoline (15). The present study was undertaken in an effort to measure the effects of large doses of intravenous priscoline on cerebral blood flow, metabolism, and other cerebral metabolic functions in man.

Relationship of Hippuric Acid Excretion to Urinary Volume.

Summary The rate of excretion of hippuric acid is independent of urine volume, indicating that the present standards for the interpretation of the hippuric acid test are valid. It is suggested that hippuric acid excretion is a function of the renal tubules.