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Lymph was collected from a vessel in the hilar region of the kidney in 33 dogs. Care was taken to leave other renal lymphatics undisturbed. Renal lymph and urine were collected continuously and arterial blood periodically. The renal lymph-to-arterial plasma ratios of all endogenous substances measured were essentially unity except urea, total protein, and calcium, whose ratios were less than one. Intravenously infused PAH and inulin appeared in renal lymph in concentrations of 58 and 80%, respectively, of their concentrations in arterial plasma. In five dogs, both hilar and capsular lymph was collected simultaneously. Sodium concentrations were similar in these samples and in neither was sodium more concentrated than in arterial plasma.

A method was developed for the demonstration of intrarenal lymphatics by the retrograde injection of contrast medium directly into capsular or hilar lymphatic trunks. Utilizing this method in the dog, intrarenal lymphatics were found to be distributed primarily along arcuate blood vessels and in interlobular spaces with small branches closely associated with Bowman’s capsule. These lymphatic vessels were found to be continuous with both capsular and hilar lymphatic trunks. Data derived from a horse and a calf support the findings in dog concerning periglomerular lymphatics and the interlobular distribution respectively. Although this study does not preclude the existance of medullary lymphatics, we have never observed injected lymphatics in this area. On the basis of the lymphatic distribution found in this study, renal lymph is derived primarily from fluid formed in the periarterial spaces along with a component derived from the immediate vicinity of Bowman’s capsule.

Murexine (urocanoylcholine, [2-f3-imidazol-4(5)-ylacryloyloxyethyl] trimethylammonium bromide) has been shown to possess ganglion stimulating and neuromuscular blocking actions in cat, dog and rat. The blockade has been shown to be of the depolarizing type both on the basis of the resemblance of the pharmacological properties of the substance to that of known depolarizing blocking agents, and also directly by recording the depolarization produced in the endplate region of the gracilis muscle of the rat.The recent appearance of several reports on the pharmacology of murexine (urocanoylcholine, [2-fi-imidazol-4(5)-ylacryloyloxyethyl] trimethylammonium bromide) (Erspamer and Glisser, 1957;Grelis and Tabachnick, 1957;Quilliam, 1957) has prompted us to give a fuller account of some experiments carried out with this compound in 1955 which have so far been reported only in abstract form (Keyl and Whittaker, 1955).The compound is of interest in being a naturally occurring choline ester. It was first identified by Erspamer and Benati (1953) in three Mediterranean species of whelks of the family Muricidae and later in three other North Atlantic Muricidae (Whittaker and Michaelson, 1954; Keyl, Michaelson, and Whittaker, 1957).Our experiments confirm that murexine has a ganglion stimulating and neuromuscular blocking action. We have also demonstrated by means of the scanning electrode technique of Burns and Paton (1951) (1951). Potentials were led through cathode followers into a D.C. amplifier and recorded photographically after display on a double beam cathode ray tube. To facilitate the interpretation of the record, the beam recording action potentials was made to move in an axis at right-angles to that recording the endplate potentials.

The purpose of this study was to investigate the hormonal and renal response to plasma volume expansion in the ketamine-anesthetized rhesus monkey. The blood volume was determined in nine animals and found to be 6% of the body weight. Six monkeys received isoncotic isotonic fluid amounting to 25% of the blood volume. Plasma volume expansion led to significant decrease in the plasma concentrations of antidiuretic hormone (46.7%) and aldosterone (78.4%) as well as plasma renin activity (50.0%). The mean arterial pressure, plasma osmolality, and plasma concentrations of Na+ and K+ were unaffected by plasma volume expansion. However, renal plasma flow, glomerular filtration rate, the excretion of Na+ and K+, and urine flow increased. It was concluded that, in the ketamine-anesthetized rhesus monkey, circulating hormones contribute to blood volume homeostasis presumably through a neural mechanism similar to that observed in dogs and humans.

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