pituitrin and Acid-Base-Imbalance

The rate of acid excretion by the kidney appears to be determined by factors regulating the site and the rate of sodium reabsorption, rather than by a homeostatic mechanism that responds to systemic pH. This hypothesis, although unconventional, is supported by much experimental evidence, and it accounts for a wide variety of clinical and physiologic findings that heretofore have been difficult or impossible to explain.

Topics: Absorption; Acid-Base Imbalance; Acidosis; Alkalosis; Ammonia; Animals; Bicarbonates; Carbon Dioxide; Cations; Chronic Disease; Dogs; Homeostasis; Humans; Hydrogen-Ion Concentration; Hypercapnia; Kidney; Kidney Tubules; Minerals; Nephrons; Sodium; Vasopressins

The adequate management of brain dead donors on an Intensive Care Unit (ICU) is one of the major key points for a successful transplantation of harvested organs. In addition to an invasive monitoring like in any other ICU patient these patients needs a meticulous attention to their hemodynamic. The early administration of desmopressin to treat diabetes insipidus, a differentiated use of fluid resuscitation and a distinct catecholamine support are special features of an appropriate basic treatment. The administration of corticoids has to be considered if a sufficient circulation can not be regained.

Topics: Acid-Base Imbalance; Brain Death; Hemodynamics; Humans; Hydrocortisone; Thyroid Hormones; Tissue Donors; Vasopressins

Topics: Acetazolamide; Acid-Base Imbalance; Biological Transport; Diuretics; Drug Resistance; Ethacrynic Acid; Furosemide; Humans; Hydrochlorothiazide; Hyperkalemia; Hypernatremia; Hypokalemia; Hyponatremia; Indapamide; Kidney Tubules, Distal; Kidney Tubules, Proximal; Loop of Henle; Metolazone; Osmolar Concentration; Spironolactone; Triamterene; Vasopressins

The relative effects of 3 stimuli in the release of vasopressin (VP) by the fetus were examined in 19 chronically instrumented fetal lambs, 118-135 days gestational age. The fetus was exposed to: 1) 30-min administration of 10% O2 to the pregnant ewe, 2) 20 min of partial occlusion of the umbilical cord, or 3) 2 min of complete occlusion of the umbilical cord. Twelve studies were conducted for each of these experimental protocols. The rises (mean +/- SE) in plasma VP in the 3 groups were 29.9 +/- 8.9, 48.9 +/- 11.5, and 157.8 +/- 12.5 pg/ml, respectively; the corresponding falls in PaO2 were 9.2 +/- 0.7, 7.7 +/- 0.9, and 12.7 +/- 1.2 mm Hg. pHa did not change in the group receiving 10% O2, fell by 0.11 +/- 0.02 and 0.14 +/- 0.01 after partial and complete occlusion of the umbilical cord. The rises in mean arterial pressure were 6 +/- 2.2, 10 +/- 1.9, and 23 +/- 3.1 mm Hg, respectively, at the end of the 3 procedures. The rise in plasma osmolality ranged from 2-8 mosmol/kg in all 3 groups. Linear regression analyses showed that log VP was negatively correlated with PaO2 (r = -0.827; P less than 0.01) and pHa (r = -0.706; P less than 0.01) and positively correlated to mean arterial pressure (r = 0.607; P = 0.01), but was not significantly correlated to plasma osmolality. Our present findings suggest that hypoxemia and acidemia are associated with and may both be potent stimuli for VP release in the hypoxic fetus. Increased release together with decreased rate of metabolism by the placenta offer an explanation for the very high VP levels found in the neonate after labor and delivery.

Topics: Acid-Base Imbalance; Animals; Blood Gas Analysis; Female; Fetal Blood; Fetus; Gestational Age; Hypoxia; Pregnancy; Sheep; Vasopressins

Topics: Acid-Base Imbalance; Acidosis; Alkalosis; Animals; Body Water; Bucladesine; Bufo marinus; Drug Interactions; Female; Indomethacin; Male; Urinary Bladder; Vasopressins

Topics: Acid-Base Imbalance; Adult; Alcoholism; Beer; Heart Diseases; Humans; Hyponatremia; Liver Diseases; Male; Nutrition Disorders; Vasopressins

A reversed diurnal excretory rhythm of water, creatinine and electrolytes was observed in a woman with fluid retention that first appeared following a head injury 21 years previously. Synthetic oxytocin injections were given on the premise that she had a selective deficiency of oxytocin with normal vasopressin production. This treatment produced a diuresis and restored a normal excretory rhythm of water, creatinine and electrolytes. Inulin and PAH clearance studies showed that oxytocin increased the daytime glomerular filtration rate. These results suggest the possibility that oxytocin has an additional non-obstetrical physiologic function, viz. the regulation of the normal diurnal rhythm of glomerular filtration rate.

Topics: Acid-Base Imbalance; Body Fluids; Circadian Rhythm; Diuresis; Diuretics; Electrolytes; Female; Glomerular Filtration Rate; Humans; Inulin; Kidney; Oxytocics; Oxytocin; Periodicity; Vasopressins; Water; Water-Electrolyte Balance; Water-Electrolyte Imbalance