bluuebunny/crossref_metadata_2025 huggingface dataset:
FLUID INTAKE AND EXCHANGEABLE BODY SODIUM OF NORMAL AND ADRENALECTOMIZED RATS GIVEN VARIOUS CONCENTRATIONS OF SALINE TO DRINK
Authors: Edmonds C. J.
Published: December 2014

Normal rats drank increasing quantities as the salt content of their drinking water was increased. Adrenalectomized rats drank much less than normal rats when given 2 per cent or 2·3 per cent saline and some drank so little of these solutions that they died from dehydration. Cortisone restored the volume of hypertonic saline drunk to the normal level. Despite the rise in sodium chloride intake, no increase of exchangeable body sodium occurred in the normal or adrenalectomized rats when they were given hypertonic saline to drink. Serum sodium concentration increased to a small extent.
ESTEROLYTIC AND LIPOLYTIC ENZYMES OF MACROPHAGES
Authors: Day A. J. , Harris Pamela M.
Published: December 2014

Macrophages obtained from the peritoneal cavity of rabbits have been shown to possess both esterolytic and lipolytic activity. Esterase was demonstrated by the hydrolysis of both tributyrin and β‐naphthyl acetate by macrophages. The esterase was inhibited by sodium taurocholate, sodium fluoride, quinine hydrochloride and by low concentrations of eserine, and was probably pseudocholinesterase. The optimal pH for esterase activity was 7·5. Lipase was demonstrated by the hydrolysis of chyle triglycerides by macrophage homogenates and by the increased hydrolysis of β‐naphthyl laurate by macrophages, in the presence of sodium taurocholate.
OXIDATION OF 14C‐LABELLED CHYLOMICRON FAT AND 14C‐LABELLED UNESTERIFIED FATTY ACIDS BY MACROPHAGES IN VITRO AND THE EFFECT OF CLEARING FACTOR
Authors: Day A. J.
Published: December 2014

The oxidation by macrophages of 14C‐labelled chylomicron fat and of 14C‐labelled sodium palmitate was investigated by incubating these substances with rabbit macrophages in vitro and collecting the 14CO2 produced. Partial oxidation of both 14C‐labelled chylomicron fat and 14C‐labelled sodium palmitate occurred. The amount of fatty acid oxidized was approximately the same whether it was presented as chylomicron fat or as sodium palmitate.

Clearing factor, added to the medium as post‐heparin plasma, inhibited the oxidation of 14C‐labelled chylomicron fat by macrophages. This inhibition was not influenced by the replacement of the calcium ions removed by the unesterified fatty acids formed during clearing. Clearing factor inhibited the oxidation of 14C‐labelled sodium palmitate only if chyle was added to the incubation medium. An excess of sodium palmitate or the addition of glycerol did not reduce the oxidation of sodium palmitate by macrophages.

Thus macrophages can oxidize both chylomicron esterified fatty acids and unesterified fatty acids to CO2. There were substances produced during the clearing of chyle by post‐heparin plasma, which inhibited the oxidation of fatty acids by macrophages.
THE INFLUENCE OF THE OCCIPITO‐VERTEBRAL ANASTOMOSES ON THE CAROTID SINUS REFLEX OF THE SHEEP
Authors: Waites G. M. H.
Published: December 2014

It has been shown that in sheep the carotid sinus nerve innervates the artery at the origin of its occipital branch and that the carotid bodies are in the same region. Occlusion of the carotid arteries causes a fall in sinus pressure and a reflex rise in general blood pressure, but blood from the vertebral circulation flows through the occipital arteries and into the sinus region sufficiently rapidly to modify and reduce these effects. These are demonstrable in conscious sheep with exteriorized carotid arteries and so, to obtain reliable blood pressure records from an exteriorized carotid, it is necessary to denervate the sinus on the same side.
ELECTRON MICROGRAPHIC OBSERVATIONS ON THE EMIGRATION OF LEUCOCYTES
Authors: Marchesi V. T. , Florey H. W.
Published: December 2014

Electron micrographs have been made of small venules in the rat's mesentery after exposure to mild mechanical trauma. Stages in the migration of blood cells are illustrated.

Polymorphonuclear leucocytes seem sometimes to penetrate the endothelium at or near cell junctions, but they may also be able to penetrate the endothelial cytoplasm at other points. After the passage of the leucocytes through the endothelium no sign of a passage way can be seen.

The emigrating leucocytes may be held up for a time by the basement membrane of the endothelium or by the periendothelial tissues but these are eventually penetrated so that the leucocytes become free in the surrounding tissue.

Eosinophils and probably monocytes were seen passing through the vessel walls apparently in a manner similar to that of the polymorphs.

Red blood cells were seen in process of going through the endothelium but the pictures do not show whether they pass through it in holes made by leucocytes.
THE EFFECT OF FATTY ACIDS ON THE FORMATION OF THROMBI
Authors: Connor William E. , Poole J. C. F.
Published: December 2014

When the sodium salts of certain fatty acids were added to rat blood in vitro, the production of artificial thrombi by a modification of Chandler's method was significantly altered: thrombus‐formation time was accelerated greatly and longer thrombi were produced.

Straight‐chain, saturated fatty acids with sixteen to twenty‐six carbon atoms were strongly active. Short‐chain fatty acids, C 6 and C 7, were inactive. The four long‐chain, unsaturated fatty acids tested, oleic, elaidic, ricinoleic, and arachidonic, were inactive or very nearly so. The activity of a long‐chain fatty acid such as stearate, was reduced by the addition of methyl groups.
THE STRUCTURE OF NORMAL SMALL LYMPHATICS
Authors: Casley‐Smith J. R. , Florey H. W.
Published: December 2014

The structure of the lymphatic capillaries and lacunes as seen by electron microscopy was similar to that of the blood capillaries of, for instance, skeletal muscle. All the lymphatic endothelial cells contained many vesicles and caveolæ intercellulares. No fenestrations in the endothelium were seen, but some intercellular junctions were patent, especially in diaphragmatic lacunes. The basement membrane was less regular than that of blood capillaries or of mesothelium and in many places, especially in diaphragmatic lacunes, it appeared to be absent.

Carbon and ferritin were injected into the peritoneal cavity and could be seen in the lumen of diaphragmatic lacunes, in vesicles in mesothelium and endothelium, and in patent junctions between endothelial cells. Deposits of ferritin without an encircling membrane were also seen in the cytoplasm.
SOME CAUSES OF VARIATION OF BODY TEMPERATURE IN MICE
Authors: McLaren Anne
Published: December 2014

Colon temperatures of mice belonging to two inbred strains were determined. Mice of the C3H strain showed greater individual consistency over a period of 10 days than did C57BL mice, and differed also in showing marked effects of age and lactation on body temperature. In both strains there was a difference between the sexes in temperature, but in opposite directions in the two strains.

The precise control of body temperature in the C3H strain seems to depend on long‐term physiological factors, whereas in the C57BL strain it is influenced more by short‐term variations in internal or external conditions.

The differences in body temperature between the two strains are not adequate to account for the maternal effect on vertebral type observed in the F1 progeny of reciprocal crosses between the strains.
THE EFFECT OF WORK AND CLOTHING ON THE MAINTENANCE OF THE BODY TEMPERATURE IN WATER
Authors: Keatinge W. R.
Published: December 2014

Twelve young naval ratings were repeatedly immersed in water at temperatures between 5 and 37·8° C. Their temperatures, both rectal and œsophageal when measured, fell more rapidly when they worked than when they stayed still in water at 5 or 15° C. This was so whether the men worked as hard as possible or at a slower rate, whether they wore clothes or not, and whether or not the water (at 15° C.) was stirred when they were still. The fattest man suffered relatively small falls in rectal temperature at both 5 and 15° C. whether he worked or was still. Work had no significant effect on the rectal temperatures of unclothed men in water at 25° C. and caused a rise in water at 35° C.

Work had no important effect on the falls in surface or mean temperature during 20‐min. immersions at 5° and 15° C. when the men were unclothed and the water (in the still experiments) was stirred, but it increased the falls in mean temperature when the immersions lasted 40 min. and increased both when the men were clothed. Clothing substantially reduced the men's falls in both surface and deep temperature, particularly in water at 5° C. This effect was prolonged when the men were still, but when they worked it was relatively slight after the first few minutes.
A THEORETICAL AND EXPERIMENTAL ANALYSIS OF ANOMALIES IN THE ESTIMATION OF PULMONARY DIFFUSING CAPACITY BY THE SINGLE BREATH METHOD
Authors: Jones R. S. , Meade F.
Published: December 2014

The theoretical basis of the single breath method of estimating pulmonary diffusing capacity is re‐examined and the mathematical analysis is extended to include the behaviour of an ideal model during inspiration and expiration. Equations derived, describing the changes of carbon‐monoxide concentration in the alveolar gas during inspiration, breath holding and expiration, are consistent with data from experiments on a normal subject. The analysis is applied to the problem presented by the observation of Forster and co‐workers using their modification of Krogh's single breath technique that the estimate of pulmonary diffusing capacity was dependent on experimental procedure, varying with length of breath holding, the time taken to inspire the test mixture and the manner in which the sample of alveolar gas was taken. The theoretical and experimental evidence presented shows that these anomalies can arise from aneglect of the effects of alveolar volume changes inescapably associated with the test and may be eliminated by a simple allowance for the times of inspiration of test gas and expiration of sample. Practical conclusions include the desirability of using small alveolar gas samples, collected as early as possible during expiration. A method is described in which 85‐ml. samples are collected in evacuated tonometers. The relevance of the findings to the estimation of pulmonary capillary blood volume and the diffusing capacity of the pulmonary membrane is also discussed.
THE FREE MYO‐INOSITOL CONCENTRATION OF ADULT AND FETAL TISSUES OF SEVERAL SPECIES
Authors: Battaglia Frederick C. , Meschia Giacomo , Blechner Jack N. , Barron Donald H.
Published: December 2014

The presence of myo‐inositol in adult and fetal tissues has been confirmed by crystallization, and determination of the molecular weight, melting point, percentage composition and chromatographic purity of the crystals.

A pattern of distribution of myo‐inositol among the tissues of a given animal was observed; cerebellar and cortical tissue having the highest concentration and liver and skeletal muscle, the lowest. This pattern was found to be comparable in both adult and fetal tissues with the exception of cardiac muscle. Several species differences in distribution were noted.
SURGICAL TECHNIQUES FOR THE COLLECTION OF LYMPH FROM UNANÆSTHETIZED SHEEP
Authors: Lascelles A. K. , Morris Bede
Published: December 2014

Surgical techniques for collecting lymph from the thoracic, hepatic, intestinal and mammary lymph ducts of sheep are described. Recirculating thoracic and intestinal lymph fistulæ were maintained for periods of up to 2–3 weeks. At the end of this time the sheep were in good condition and had lost little weight. Liver lymph was collected for 2–3 weeks and mammary lymph for periods up to 10 weeks. The lymph from these preparations was collected into a plastic bottle sutured to the animal's flank. The sheep with hepatic lymph fistule showed a loss in weight after about 7–10 days but remained in good health for 2–3 weeks. The drainage of lymph from the udder for periods up to 10 weeks had little effect on the general condition of the sheep.
THE FLOW AND COMPOSITION OF LYMPH FROM THE MAMMARY GLAND IN MERINO SHEEP
Authors: Lascelles A. K. , Morris Bede
Published: December 2014

An investigation has been made of the flow and composition of lymph collected from the mammary lymph duct of lactating and dry merino ewes. Lymph flowed at the rate of 20–40 ml./hr. in ewes in early lactation and 2–6 ml./hr. in dry ewes. The rate of lymph flow was highest in those ewes producing the most milk. Maximum rates of flow of 50–180 ml./hr. were recorded for short periods of time in lactating ewes when they were suckled or when they were milked. In lactating ewes, the mammary lymph ducts contributed up to 20–30 per cent of the total thoracic duct lymph flow and up to 10–20 per cent of the total thoracic duct lymphocyte output per day.

In general, the composition of udder lymph resembled lymph collected from areas such as the head and neck and limbs. In lactating ewes there was a large plasma‐lymph concentration gradient for both unesterified fatty acids and triglycerides and this suggested that these substances were being utilized by the mammary gland.

Estimates have been made on the size of the interstitial fluid pool drained by the mammary lymph duct in lactating and dry ewes. Values of 100–220 ml. for ewes in early lactation and 20–60 ml. in dry ewes are reported. These findings are discussed in relation to the exchange of substances between the plasma and the mammary gland during the synthesis and secretion of milk.
THE EFFECT OF BRONCHIAL VASCULAR SYSTEM PERFUSION ON THE PULMONARY VASCULAR RESISTANCE (PVR) IN ISOLATED LUNG LOBES OF THE DOG
Authors: de Burgh Daly I. , Waaler B. A.
Published: December 2014

Previous experiments with isolated perfused lungs have been criticized on the grounds that the pulmonary vascular resistance (PVR) obtained has been far above the upper limit for that of a normal resting animal. In the experiments described here the PVR of lungs perfused through the pulmonary circulation alone was within normal limits. Additional perfusion of the bronchial circulation increased the PVR but not beyond the normal range.

Evidence is presented which suggests that handling of the lungs before perfusion is started gives rise to a pulmonary vasoconstrictor substance derived directly or indirectly from the bronchial circulatory system but not from the pulmonary circulation. Liberation of small amounts of this vasoconstrictor substance may be responsible also for the higher PVR values observed in nonhandled lungs in which the bronchial circulation is perfused.
THE DEVELOPMENT, STRUCTURE AND COMPOSITION OF THE OPTIC NERVE OF XENOPUS LÆVIS (DAUDIN)
Authors: Gaze R. M. , Peters A.
Published: December 2014

The optic nerves of tadpoles and adults of the toad Xenopus lævis (Daudin) have been examined with the electron microscope. The total number of nerve fibres was counted and their diameters measured at various stages of development and the relation between glial cells and nerve fibres is described. In tadpoles at late stage 49, the earliest at which consistent visual responses, as determined by an optokinetic drum, were obtained, the first myelinated fibres are found within the nerve. At this stage the tectum is apparently undifferentiated and shows none of the layering of the adult tectum. Previous to this, the nerve is composed entirely of unmyelinated fibres, which in the early stage 49 number about 5000. These increase throughout development, until in the adult nerve about 6000 myelinated and 28,250 unmyelinated fibres are present.
THE ELIMINATION OF MOUSE AND BOVINE GLOBULINS FROM THE CIRCULATION OF NEWBORN AND ADULT MICE
Authors: Pace M. Geraldine , Dresser D. W.
Published: December 2014

The rate of elimination of 131I labelled serum proteins from the circulation of mice has been calculated from estimations of radioactivity in the whole body and in samples of serum. In adult mice heterologous globulins are eliminated faster than homologous globulins, but in suckling mice no clear interpretation could be made of the results. It has also been shown that any one protein is eliminated faster by outbred mice than by CBA mice; this is certainly so in adults and possibly also in suckling mice.

Estimations of the half‐lives of l31I labelled proteins in suckling mice by counts of the radioactivity of the whole body, have been found to be inaccurate. This method gives longer half‐lives than counts of radioactivity of serum. This difference decreases with age so that in 3‐month‐old adult mice the half‐lives obtained by the two methods do not differ significantly. The unreliability of counts of the whole body may be due to the recirculation of the iodine label. A large amount of non‐protein‐bound radioactivity has been demonstrated in the gut and gut contents of sucklings, the amount of free label falling with increasing age. Counts of serum of sucklings show a slight decrease in the rate of elimination of 131I labelled bovine gamma globulin with increasing age, although it has not been possible to determine if this is a real difference in the rate of elimination of the protein, or is an artefact due to a small amount of reincorporation of 131I into the serum proteins of suckling mice.
FACTORS REGULATING PLASMA TOTAL IRON BINDING CAPACITY IN THE RAT AND RABBIT
Authors: Morgan E. H.
Published: December 2014

Tn order to determine which of the three factors, rate of erythropoiesis, supply of erythropoietic stimulating factor or tissue oxygen supply, was involved in the regulation of plasma total iron binding capacity (TIBC) in the rat and rabbit these three factors were varied independently of each other. The methods used to do this included X‐irradiation and starvation and the administration of phenylhydrazine, colchicine, viable erythrocytes and plasma from normal and anæmic rabbits. The changes found in TIBC suggested that the balance between tissue oxygen supply and demand may be the most important factor.
THE REGRESSION IN SIZE OF THE HYPERTROPHIC REMAINING KIDNEY AFTER HYPOPHYSECTOMY IN RATS
Authors: Astarabadi T.
Published: December 2014

Forty‐five albino rats had one kidney removed and were then divided into three groups, A, B, C, of fifteen rats each. Two weeks later group B was hypophysectomized and group A had their remaining kidney removed and weighed; group C received no further treatment. After another 2 weeks the remaining kidneys of groups B and C were removed and weighed. The remaining kidneys of the hypophysectomized rats underwent considerable regression in size. The results of the experiment suggest the presence of a renotrophic principle in the hypophysis which is required for the compensatory renal hypertrophy.
THE ABSORPTION OF SOME B‐GROUP VITAMINS BY SURVIVING RAT INTESTINE PREPARATIONS
Authors: Turner J. B. , Hughes D. E.
Published: December 2014

Everted sacs of rat small intestine transferred mixtures of B‐group vitamins (nicotinic acid, pantothenic acid, biotin, thiamine, folic acid and vitamin B12) from mucosal to serosal side and in the reverse direction at approximately equal rates. No marked concentration changes occurred when equal concentrations of vitamins were placed on both sides. There was no evidence of concentration of any of the vitamins against a concentration gradient. The movement of vitamins was not markedly affected by the addition of substrates (glucose, α‐oxoglutarate, acetate and pyruvate) or inhibitors (azide, cyanide, phlorrhizin). The magnitude of water movements bore no simple relationship to vitamin movements. Substantially the same results were found with segments of rat intestine through which the vitamins were circulated and with sacs of hamster intestine. It is concluded that the absorption of vitamins from the intestine is by passive diffusion and these rates are sufficient to account for the daily uptake of vitamin from the diet.
ELECTRICAL THRESHOLDS OF UNIMPALED CORTICOSPINAL CELLS IN THE CAT
Authors: Hern J. E. C. , Phillips C. G. , Porter R.
Published: December 2014

Previous measurements of cortical electrical thresholds for firing impaled pyramidal cells in the cat have now been checked on unimpaled cells, whose discharges were led from their axons in cervical spinal white matter. The thresholds are higher than those for impaled cells, but are still below the threshold for movement. Long pulses evoked repetitive discharges. Currents causing movement caused firing of cells whose lowest‐threshold foci were as far as 7 mm. distant from the lowest‐threshold motor “point”. Currents of intermediate strengths evoked synaptic potentials in spinal motoneurones. Thresholds and timing of pyramidal impulses and of synaptic potentials afford no evidence of monosynaptic connexion between pyramidal axons and motoneurones, such as occurs in primates.
TWO TYPES OF CORONARY VASOMOTOR REFLEXES
Authors: Szentiványia M. , Juhász‐Nagy A.
Published: December 2014

There are two receptor zones in the area of the coronary system. The reflex elicitable from the coronary sinus by stretching its wall serves to set blood pressure to a new level, whereas the coronary depressor reflex is similar in its properties to the simple depressor reflexes and as such serves to maintain blood pressure at a given level. The receptors of the latter reflex are located elsewhere in the left coronary bed, but not in the coronary sinus.

The coronary sinus reflex is characterized by its all‐or‐nothing nature: wall‐stretching over the threshold does not further modify the reaction.

In contrast with this, the size of the coronary depressor response is proportionate to the increase of pressure.

Another feature in which coronary sinus reflex differs from the coronary depressor reflex is its trigger‐like function; i.e. the reaction, once elicited, may persist even after the stimulus applied is no longer active.

In spite of the differences in their properties, the two reflexes form a functional unit, insofar as the coronary depressor reflex is capable of modulating the effect of the coronary sinus reflex.

On the basis of the experimental evidence, one branch of the left thoracic vagus may be assumed to play a specific role in the elicitation of these reflexes.
THE GROWTH AND MITOSIS OF HUMAN SMALL LYMPHOCYTES AFTER INCUBATION WITH A PHYTOHÆMAGGLUTININ
Authors: Marshall W. H. , Roberts K. B.
Published: December 2014

Suspensions of human peripheral blood lymphocytes have been obtained by centrifuging blood in which the red cells were agglutinated with a phytohæmagglutinin (PHA). After 2 and 3 days culture, these suspensions frequently contained numerous large dividing cells. It is thought that it is the small lymphocyte which grows during the period of culture into a cell capable of dividing since on occasion greater than 98 per cent of the cells in the original suspension were small lymphocytes.

The changed lymphocytes are pyroninophilic. Electron micrographs of these cells show no extensive endoplasmic reticulum.
PLASMA IRON BINDING CAPACITY AND IRON STORES IN ALTERED THYROID METABOLISM IN THE RAT
Authors: Morgan E. H.
Published: December 2014

Male rats were treated for 6 weeks with either thyroxine or propylthiouracil, each in two dosage levels. Then their oxygen consumption, blood hæmoglobin, plasma iron and total iron binding capacity (TIBC), and liver and spleen storage iron were measured and compared with the values from untreated control rats. The most striking changes were in TIBC which increased markedly with thyroxine and diminished with propylthiouracil treatment. There was a statistically highly significant direct correlation between TIBC‐values and oxygen consumption. It was concluded that in the rat one of the factors regulating plasma TIBC is the balance between tissue supply and demand for oxygen.
INTERACTION OF CO2 AND HYPOXIC STIMULI ON VENTILATION AT HIGH ALTITUDE
Authors: Tenney S. M. , Remmers J. E. , Mithoefer J. C.
Published: December 2014

The interaction of O2 and CO2 on the control of ventilation has been studied by a rebreathing technique in three healthy young male subjects, first under sea level conditions, then following 2 weeks' acclimatization to an altitude of 14,250 ft. The following results were observed: (a) at high altitude the family of response curves were shifted to lower values of alveolar CO2, and all response curves had a steeper gradient δVE/δPAACOACO2 than at sea level; (b) hypoxia potentiated the response to hypercapneic stimulus to about the same extent at sea level and at high altitude; (c) the ventilatory response to hypoxia was identical at sea level and at high altitude when PAACOACO2 was held at the normal air breathing value for the two conditions; but (d) potentiation of ventilatory response to hypoxia at high altitude occurred with smaller increments of CO2 than at sea level. This was interpreted to mean that H+ is an important factor in the mechanism of hypercapneic potentiation of hypoxic stimulus.
THE LOCALIZATION OF ADRENALINE IN ADRENERGIC NERVES IN THE FROG
Authors: Falck B. , Häggendal J. , Owman Ch.
Published: December 2014

The frog heart contains high amounts of adrenaline, only little noradrenaline and insignificant amounts of dopamine and 5‐hydroxytryptamine. By means of a highly sensitive and specific fluorescence method for the cellular detection of certain monoamines, it has been shown that adrenaline is located in adrenergic nerves. Investigations on the innervation of the kidney and urinary bladder as well have furnished evidence that adrenaline is the adrenergic transmitter in the frog.
THE EFFECT OF DIVERTING BILE AND PANCREATIC JUICE ON THE INHIBITION OF GASTRIC MOTILITY BY DUODENAL STIMULI IN THE UNANÆSTHETIZED RAT
Authors: Morgan R. G. H.
Published: December 2014

The motility of the gastric antrum was recorded with a saline manometer in normal rats and in rats in which the bile and sometimes also the pancreatic juice had been diverted to the exterior. The inhibitory effects of a variety of substances infused into the duodenum were tested. There was an inhibitory response to 50 per cent glucose, 0·2N HCl or 20 per cent ethanol, which was not altered by diversion of bile or both bile and pancreatic juice. The inhibitory action of triglyceride was lost within one hour of diversion of bile, but could be restored by adding bile salts or Tween 80 to the infused fat. Neither bile salts nor Tween 80 restored the response to triglyceride in the absence of both pancreatic juice and bile. Oleic acid was an active inhibitor of antral motility in all groups, but was more effective when emulsified. Bile salts alone had no effect on gastric motility in the doses used when infused intraduodenally or intravenously.

These results suggest that the material causing the inhibition of gastric motility after a fatty meal is not the triglycerides, but the free fatty acids liberated and emulsified under the combined action of bile and pancreatic juice.
THE EFFECT OF MATERNAL OVERHYDRATION ON THE RAT FŒTUS
Authors: Seller Mary J.
Published: December 2014

Intravenous administration of 50 ml./kg. of water to pregnant rats resulted significant increase in water content of the maternal blood and muscle. This was accompanied by a significant rise in fœtal hæmatocrit values. There was change in the water content of the total fœtus, or amniotic sac, amniotic fluid and placenta. Increasing the amount of injected water to 75‐100 ml./kg. resulted in an increase in water content of the total fœtus and placenta with amniotic sac. Administration of 50 ml./kg. of isotonic saline to pregnant rats did not affect the water content of the fœtus, amnion or placenta.
RHYTHMIC EXCITATION OF A STRETCH REFLEX, REVEALING (a) HYSTERESIS AND (b) A DIFFERENCE BETWEEN THE RESPONSES TO PULLING AND TO STRETCHING
Authors: Roberts T. D. M.
Published: December 2014

When sinusoidally fluctuating tensions were applied to the soleus muscle of a decerebrate cat, plots of tension against length showed a hysteresis loop, implying damping. Various tensions and frequencies of oscillation were used, with and without simultaneous head‐tilting or inhibition of the stretch reflex. The damping was not frequency‐dependent (i.e. not viscous or due to velocity feedback). The pattern of the loops for overlapping ranges of tension indicated a “distributed simple friction” mechanism. The way the loops shifted during change of gamma bias indicated that the damping was located in the series‐elastic elements. During imposed length‐changes the response curve shifted sporadically along the tension axis and sudden twitch‐like increases in tension occurred in an unpredictable fashion. In contrast, the responses to tension‐changes were more consistent. This difference was most marked when other reflex effects were simultaneously elicited, e.g. by head‐tilting. The effects are accounted for by defining the stretch reflex as “a reflex increase in the stiffness (δT/δL) of a muscle in response to increased tension on its spindles”. The sequence of changes in the "clasp‐knife" response can also be explained in this way.
HISTOCHEMICAL DEMONSTRATION OF MYOEPITHELIAL CELL ACTIVITY
Authors: Travill A. A. , Hill M. F.
Published: December 2014

The specific localization of alkaline phosphatase in the myoepithelial cells of the mouse submaxillary gland was employed to demonstrate the activity of these cells following stimulation. The submaxillary glands of adrenaline‐treated mice contained myoepithelial cells whose diameter was significantly smaller than comparable sections from control or pilocarpine‐treated animals. This observation is discussed and related to the presumed contractility of the myoepithelial cells.
INTRACELLULAR MUCOPOLYSACCHARIDES IN THE NORMAL HUMAN BRONCHIAL TREE
Authors: McCarthy Ciaran , Reid Lynne
Published: December 2014

Mucus‐secreting cells in the human bronchial tree have been studied by histochemical methods, using Alcian blue and periodic acid‐Schiff and also aldehyde Fuchsin (AF) and Alcian blue (AB), in the order of AF/AB and AB/AF and in association with treatment by cetyl‐triethyl‐ammonium‐bromide and methylation‐saponification. By a combination of stains, the acid mucopolysaccharides have been distinguished from the neutral: neuraminic acid has been located by using consecutive sections stained as above, one of which had previously been treated with neuraminidase. Certain deductions about the nature of Alcian blue staining are made.

Neutral mucopolysaccharide is mainly confined to the granular cells, acid mucopolysaccharide to distended cells. Some of the latter contain neuraminidase‐susceptible acid mucopolysaccharide, while in others it is only partially susceptible; the remaining acid mucopolysaccharide is likely to be neuraminidase‐resistant neuraminic acid. Surface epithelium, ducts and glands each have a characteristic distribution of the various cell types. The findings suggest a cycle of secretion.
CONTRIBUTION TO THE STUDY OF LEUCOCYTE MIGRATIONS
Authors: de Vargas-Linares Clara E. Roig , Burgos Mario H.
Published: December 2014

The study of the structure of the vaginal mucosa of the hamster during the sexual cycle reveals, as in other rodents, that during metestrus numerous leucocytes abandon the blood vessels and pass through the vaginal epithelium into the vaginal contents. This migration, which starts a few hours after ovulation, was studied by means of the electron microscope.

The leucocytes pass through the endothelial wall of the capillaries, apparently through the intercellular junctions. They cross the lamina propria and the basement membrane of the epithelium without permanent change of either structure. The leucocytes penetrate the intercellular spaces by means of pseudopodia which appear to separate the desmosomes. As soon as the leucocytes occupy the intercellular space, they dilate it appreciably and the microvilli of the epithelial cells disappear over areas of contact with the leucocytes.

As the leucocyte draws away towards the vaginal surface, the epithelial cells appear to re‐establish contact between desmosomes and extend microvilli into the intercellular spaces. Two places of accumulation of leucocytes were seen in the lamina propria: one is below the epithelial basement membrane and the other is between the transitional cells near the epithelial surface.
EFFECTS OF ADRENALINE AND NORADRENALINE ON ATRIAL FIBRILLATION PRODUCED BY ACETYLCHOLINE: WITH OBSERVATIONS ON THE MECHANISM OF FIBRILLATION
Authors: Sharma P. L.
Published: December 2014

The effect of adrenaline and noradrenaline on atrial fibrillation produced by acetylcholine was studied in intact anæsthetized dogs. In addition, some observations were made concerning the mechanism of the fibrillatory activity of acetylcholine. Atrial stimulation at high rates during adrenaline and noradrenaline infusion produced flutter which persisted for several minutes after the stimulation ceased in four out of fourteen experiments. Simultaneous infusion of adrenaline or noradrenaline enhanced the fibrillatory activity of acetylcholine in all experiments.

Topical application of acetylcholine or methacholine to a part of the atrium, coupled with brief atrial stimulation at high rate produced fibrillation which was confined to the treated area, elsewhere flutter was recorded. When this treated area was functionally isolated from the body of the right atrium with a clamp, the arrhythmia persisted in the isolated part, while elsewhere sinus rhythm returned. Also, brief atrial stimulation applied to the right atrial appendage, after topical application of methacholine, produced fibrillation which was confined to the isolated area.

The mechanism of fibrillation has been discussed. It has been concluded that the cause of fibrillation resides in the atrial myocardium treated with acetylcholine, and not in the nodal tissues. Experimental observations support the concept of re‐entrant excitation as the cause of fibrillation.
THE ELECTRON MICROSCOPIC APPEARANCE OF THE KIDNEY IN HYDRATED AND DEHYDRATED RATS
Authors: Sabour M. S. , MacDonald Mary K. , Lambie Anne T. , Robson J. S.
Published: December 2014

Renal tissue from dehydrated rats forming a concentrated urine and from water‐loaded rats forming a very dilute urine has been compared by electron microscopy. The most striking and consistent difference between the two groups is the presence in the hydrated animals of marked thickening and fibrillary changes of the basement membrane of the pars recta of the proximal tubule and the descending limb of the loop of Henle. These changes are largely reversed by dehydration or by the administration of pitressin.

It seems likely that this appearance is due to hydration of the basement membrane, which becomes swollen and possibly less permeable to the outward passage of water and to the inward passage of sodium and urea. Such a change in the permeability of the membrane would interfere with the function of the loop as a counter‐current multiplier and would effectively prevent the building up of a medullary osmotic gradient and the formation of a concentrated urine. The reduction in papillary osmolality and the more rapid turnover of sodium within the medulla which is believed to occur in water diuresis could be explained on this view. The hypothesis is also compatible with the idea that vasopressin acts primarily and possibly solely on the collecting ducts.
AFFERENT IMPULSES IN THE PUDENDAL NERVES OF THE CAT
Authors: Todd J. K.
Published: December 2014

Ingoing impulses from sense organs in the anal and urethral regions of the cat were recorded in single fibres of the sacral dorsal roots.

In the anal region rapidly adapting discharges came from sense organs in the peri‐anal skin, in the lining membrane of the anal canal and in the peri‐anal tissues. There were slowly adapting stretch receptors in the external anal sphincter.

Rapid distension of the urethra gave rise to rapidly adapting discharges in the ingoing fibres. A steady flow of fluid along the urethra caused a sustained but irregular discharge of low voltage from receptors lying in the substance of the urethra.

There are typical muscle spindles in the substance of the external anal sphincter and lamellated end organs in the peri‐anal tissue. Lamellated end organs of varying sizes are in and around the wall of the urethra: the smallest lamellated end organ lies immediately under the epithelium of the lumen of the urethra.
ENDOTHELIAL PERMEABILITY‐THE PASSAGE OF PARTICLES INTO AND OUT OF DIAPHRAGMATIC LYMPHATICS
Authors: Casley-Smith John R.
Published: December 2014

The passage of particles from the peritoneal cavities of mice into their diaphragmatic lymphatics, and from these vessels into the peri‐lymphatic connective tissues has been studied. The particles used were chylomicra, carbon, lipoproteins, thorium dioxide and ferritin.

Particles passed through the endothelial layers via open intercellular junctions, small (50 m, µ) and large (0‐1‐1 µ) vesicles, and directly through the cytoplasm. Quantitative interpretation of the electron micrographs was difficult, but it was possible to observe gross differences between the amounts of the various particles which traversed the endothelium by each of these routes. The routes also varied markedly in their importance. Open junctions were of overwhelming importance for the passage of all the particles from the peritoneal cavity; some of the particles used them relatively very little when they passed out of the lymphatics. The open junctions probably alter in size with the respiratory inovements of the diaphragm. This would permit the lymphatics to act as pumps, with the flaps of endothelium as "inlet valves".

The large vesicles were of two kinds. Some contained chylomicra which they seemed to transport rapidly across the cells. Others were probably formed by the coalescence of many small vesicles and the agglutination of their contents. These large vesicles lost little material and remained in the cells for at least 12 weeks (the longest period studied). They grew larger and denser as time went by. The endothelial cells which contained these vesicles appeared eventually to leave the lymphatics and lodge in the connective tissue.
SPECTRAL SENSITIVITY OF SINGLE UNITS IN THE OPTIC TECTUAI OF THE GOLDFISH
Authors: Jacobson Marcus
Published: December 2014

Action potentials evoked by a small light in the visual field were recorded from single units in the optic tectum of the goldfish. The relative spectral sensitivity of these responses was measured by determining the threshold energy of the stimulus light at 22 wavelengths from 341 to 779 mµ.

After dark adaptation the spectral sensitivity of "on", "off" and "on‐off" units was the same, with a maximum at about 533 mµ and fitted the absorption spectrum of porphyropsin.

After light adaptation some "on" and some "off" units had a spectral sensitivity curve which fitted the absorption spectrum of cyanopsin with a maximum at about 620 mµ. Most units had a narrow photopic spectral sensitivity curve: in some units there was a single maximum, usually in the range 605‐651 mµ. but in some "on‐off" units the maximum sensitivities of "on" and of "off" responses were different. There were three classes of these units: R‐G units (sensitivity maxima at 630‐651 mµ and 497‐517 mµ), R‐B units (maxima 605‐651 mµ and 462 ±14 mµ) and Y‐B units (maxima 552‐605 mµ and 462±14 mµ). The neutral point, at which "on" and "off" responses had the same sensitivity, was at 552‐584 mµ in R‐G units, at 517‐552 mµ in R‐B units and at 497‐517 mµ in Y‐B units.

The results indicate that the goldfish has a rod pigment with its absorption maximum at about 533 mµ, and that there are at least two cone pigments with absorption maxima at about 467 mµ and 620 mµ. It is suggested that antagonism between two sets of cones, each set containing one of three pigments with absorption maxima at 467, 533 and 620 mµ could account for the observed sensitivity maxima and neutral points of R‐G, R‐B and Y‐B units.
EXTRAOCULAR PROPRIOCEPTIVE RESPONSES IN THE VI NERVE OF THE CAT
Authors: Bach‐Y‐Rita P. , Murata K.
Published: December 2014

Proprioceptive responses, produced by stretch of the lateral rectus muscle, were studied in the VI nerve of twenty‐one cats. Responses were recorded from slips teased from the nerve at its emergence from the pons; thus it is a mixed nerve in the cat. The responses from in‐series (tendon organ type) and in‐parallel (muscle spindle type) receptors were differentiated by observing the effect of electrically‐induced muscle contraction. A number of inhibitory and long latency responses to stretch were noted. A stretch reflex was noted in the VI nerve only when the eyeball and all muscles were intact.
THE EFFECT OF HYDROCHLOROTHIAZIDE ON WATER INTAKE AND PLASMA OSMOLALITY IN DIABETES INSIPIDUS IN THE RAT
Authors: Kennedy G. C. , Haguie P. , Skadhauge Erik
Published: December 2014

A fall in plasma osmolality accompanied the reduction of urine volume in rats with hypothalamic diabetes insipidus, given hydrochlorothiazide and an otherwise normal diet. The plasma concentration was not reduced with a high sodium intake, although urine volume still fell. Normal rats and hypothalamic obese rats increased their water turnover after hydrochlorothiazide, yet their plasma concentration fell. Moreover the antidiuretic response to vasopressin, which is purely renal, was also accompanied by plasma dilution; although it is self‐evident that rats which drink less are less thirsty, the reduction in thirst after hydrochlorothiazide may not be a direct result of the change in plasma osmolality.

As previously shown in patients [Kennedy and Hill, 1963] a high sodium intake increased free water clearance in diabetes insipidus but did not interfere with the reduction of polyuria by hydrochlorothiazide, whereas a high potassium intake reduced free water clearance and prevented any effect of the drug on urine volume.
THE EFFECT OF TENOTOMY ON THE STRUCTURE OF FAST AND SLOW MUSCLE IN THE RABBIT
Authors: Vrbová G. , McMinn R. M. H.
Published: December 2014

The effect of tenotomy on the structure of slow and fast muscles in the rabbit was studied histologically and histochemically. The results show (1) that denervation is associated with reduced succinic dehydrogenase activity in the muscle fibres of the slow soleus and of the fast peroneus longus (2) that tenotomy and tenotomy with spinal cord section are associated with reduced succinic dehydrogenase activity in soleus but not in peroneus longus (3) that tenotomy induces marked degenerative changes in soleus but not in peroneus longus and (4) that the degeneration in soleus can be prevented by denervation or spinal cord section. Correlation of these results with previous work [Vrbovaá, 1962 and 1963] suggests that the reduced succinic dehydrogenase activity is associated with decreased electromyographic activity. It was concluded that degenerative changes in soleus following tenotomy may possibly be due to impulses of supraspinal origin.
THE EFFECT OF BILE SALTS ON THE LYMPHATIC ABSORPTION BY THE UNANÆSTHETIZED RAT OF INTRADUODENALLY INFUSED LIPIDS
Authors: Morgan R. G. H.
Published: December 2014

Emulsified and unemulsified fat was infused intraduodenally at a steady rate in unanaesthetized rats with lymph fistulhe. The output of esterified fat in the lymph reached a steady state which was considered to mirror fat absorption from the lumen. In animals which also had bile fistulae the effect of addition or removal of sodium taurocholate was measured.

Unemulsified olive oil or oleic acid and mono‐olein sol was poorly absorbed in the absence of bile. Emulsified olive oil was better, but still incompletely, absorbed. In all these cases the addition of sodium taurocholate increased the absorption to that found in control animals with normal bile flow. Emulsified oleic acid was as well absorbed in bile fistula animals as in controls and the return or removal of taurocholate did not affect the output of esterified fat in the lymph. These results do not support a defect in epithelial re‐esterification of fatty acids in the absence of bile.
BONE MARROW BLOOD VOLUME AND TOTAL RED CELL MASS OF THE GUINEA‐PIG AS DETERMINED BY 59Fe‐ERYTHROCYTE DILUTION AND LIQUID NITROGEN FREEZING
Authors: Osmond D. G. , Everett N. B.
Published: December 2014

The blood content and circulating red cell volumes of bone marrow and lymphoid tissues have been determined by means of a 59Fe‐labelled erythrocyte technique coupled with liquid nitrogen freezing in male guinea‐pigs. The marrow blood volume represented 4·90–6·96 per cent of the total marrow volume and showed regional differences which have been partially correlated with marrow cellularity. It has been calculated that the entire bone marrow of the guinea‐pig normally contains 1·7 per cent of the whole body blood volume and 2·0 per cent of the whole body circulating red cell mass. At 3 hr. after the injection of labelled erythrocytes there was evidence of a selective pooling in the spleen and bone marrow of recipient animals.

The whole body blood volume was calculated to be 5·91 ml./100 g. body weight and the ratio of body hæmatocrit to cardiac hæmatocrit was 0·846.

A comparison of the numbers of circulating erythrocytes in marrow (isotope dilution technique) with total erythrocyte numbers determined in suspensions of disrupted marrow was in accord with the view that the non‐nucleated, non‐reticulated marrow erythrocytes are intravascular.
ON THE SYMPATHETIC INNERVATION OF THE PAROTID GLAND OF THE CAT
Authors: Nordenfelt Ivar
Published: December 2014

The postganglionic sympathetic fibres to the parotid gland of cats have been found to go, in most cases, through the middle ear in the tympanic plexus which also contains the preganglionic parasympathetic fibres. The sympathetic fibres do not, however, seem to pass with the postganglionic parasympathetic neurones to the gland in the auriculotemporal nerve.
DEVELOPMENT OF SUPERSENSITIVITY AS DEPENDENT ON THE LENGTH OF DEGENERATING NERVE FIBRES
Authors: Emmelin N. , Malm L.
Published: December 2014

The acetylcholine sensitivity of the cat's tongue in situ and of the rat's isolated diaphragm was estimated at varying time intervals after section of the motor nerve at different distances from the effector cells. In both preparations denervation supersensitivity was found to appear earlier if the nerve had been cut near the muscle than if it had been cut some distance proximal to this point.
THE EFFECT OF SEX DIFFERENCES AND GONADECTOMY ON SOME AORTIC ENZYMES OF THE RAT
Authors: Mrhovaá O. , Zemplényi T.
Published: December 2014

The activity of phosphomonoesterase I and β‐glucuronidase is higher in male than female rat aoræ, while the opposite is true for the activity of 5'‐nucleotidase, lactate dehydrogenase and perhaps also malate dehydrogenase. There is no difference between male and female rat aortæ in the activity of phosphomonoesterase II, group specific carboxylic esterase and glutamate‐oxalacetate transaminase.

In agreement with such sex differences, gonadectomy in females resulted in a drop and in males in a rise of aortic 5'‐nucleotidase and malate dehydrogenase activity. In addition, following gonadectomy male aortæ also displayed a tendency to elevated esterase activity and a clear cut rise in phosphomonoesterase activity.

The significance of these findings is discussed with particular reference to atherogenesis.