Hormonal disturbances of fluid-electrolyte metabolism under altitude exposure in man

Early alterations in fluid, electrolytes, and their regulating hormones were investigated in men exposed to 6,000 m simulated altitude (2 h-ascent, 2 h-sojourn, 2 h-return). Hematocrit and serum protein rose with elevated serum osmolality and reduced urine flow upon arrival at 6,000 m, suggesting decreased plasma volume probably due to hypotonic fluid shift to intracellular spaces. Serum K declined reflecting respiratory alkalosis. The exposure raised plasma antidiuretic hormone (ADH), plasma renin activity (PRA), serum cortisol and aldosterone. Increases both in ADH and aldosterone showed close correlations with that in cortisol, suggesting that ADH may be elevated by hypoxic stress in addition to elevated serum osmolality and decreased plasma volume, and that increased secretion of adrenocorticotropin may be the main cause of increased aldosterone, though PRA involvement cannot be excluded. These rises in ADH and aldosterone may act to retain body water, and the latter may exaggerate alkalosis; thus, these hormonal changes may be related to acute mountain sickness.     

Degenerative changes of vein grafts in preparation media: Preliminary studies by electron microscopy and fibrinolytic autography

Degenerative changes of saphenous vein grafts in four preparation media (heparinized whole blood at room temperature and 4°C, and heparinized normal saline at same temperatures) were examined by scanning and transmission electron microscopy and fibrinolytic autography. Following 60–90 min. storage in heparinized normal saline at room temperature, marked morphological changes were present in the media, accompanied by swellingof the endothelial cells, however the tunica media and adventitia were well preserved even after 120 minutes in all of the four preparation media. The decrease in fibrinolytic activity was comparable to the observed morphological changes. In heparinized whole blood at 4°C, degenerative changes were slow and mostly of a slight nature.     

Pharmacological studies of 3-[bis(3,3-diphenylpropyl)-amino]-propan-1-ol hydrochloride, (PF-244), a new cerebral vasodilator.

Pharmacological effects of 3-[bis(3,3-diphenylpropyl)-amino]-propan-1-ol-hydrochloride (PF-244) mainly on cerebral and cardiovascular systems, were studied. PF-244 indicated a potent cerebral vasodilation effect and a marked increase in oxygen supply to cerebral tissue with only weak inotropic action and depressor effect. This cerebral vasodilation was more potent and specific than that of papaverine hydrochloride in regional cerebral flow. PF-244 also indicated an antibarium action, although it did not show the properties related to the cholinergic and/or adrenergic mechanism. PF-244 appears to be one of the potent cerebral vascular dilators, and the nature of its mechanism was discussed.     

Autogenous internal iliac artery bypass in the surgical treatment of renovascular hypertension: a case report

A 24 year old female with severe renovascular hypertension resulting from bilateral fibromuscular dysplasia was successfully treated surgically. The internal iliac artery was used for a left aortorenal grafts. The right renal artery was dilated through the amputated left renal stump. Although saphenous vein graft is most commonly used, the autogenous internal iliac artery is considered a satisfactory graft in aortorenal reconstruction, especially for a young patient.     

Antagonism by droperidol of dopamine-induced relaxation in isolated dog arteries.

Dopamine caused a dose-related relaxation in helically cut strips of dog coronary and renal arteries treated with phenoxybenzamine andcontracted with prostaglandin F2 alpha. The dose-response curve to dopamine was shifted to the right by droperidol in concentrations above 3 X 10(-5) M. Adenosine-induced relaxations were not attenuated by droperidol. The dose--relaxation curve to isoproterenol was also shifted to the right by droperidol. Propranolol (10(-6) M) failed to significantly alter the dose response curve to dopamine, and in propranolol-treated preparations the antagonism by droperidol of dopamine actions was practically identical with that in control preparations. Droperidol appears to act as a reversible, surmountable antagonist to dopamine actions on dog arterial smooth muscles, and such evidence supports the hypothesis of specific dopamine receptors in dog arteries.