摘要:

AbstractA method is described for the measurement of the CO content of blood, particularly at low concentrations. The error of a single determination was 1–3 per cent of the total amount of CO (range 0.7–70 μl) present in the analyzed sample. At an ordinary CO content of about 0.1 ml CO/100 ml blood the error was about ± 0.002 ml CO/100 ml blood (S.D.). Different procedures for the release of CO from the blood were compared. With K3Fe(CN)6and H2SO4equal and slightly smaller amounts of CO were obtained than with KH(JO3)2, if blood with a low CO content was analyzed. Evidently KH(JO3)2, although less than some other chemical agents (K2Cr2O7and NaOH), causes extra CO formation from the blood. In spite of the error due to this extra CO formation there were advantages to use KH(JO3)2for analysis in higher ranges of CO concentrations, when this small error became insignificant. If extraction of CO from the blood with reagents such as K3Fe(CN)6, H2SO4or KH(JO3)2took place at a high O2partial pressure slightly larger amounts of CO were obtained than with extraction in“vacuum” or in an atmosphere of N2. The results indicate that small amounts of CO may be formed during procedures used for the release of CO from blood, probably due to oxidative break down of h

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03162.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractFollowing i.v. administration of H3palmitate labelled chylomicrons a greater amount of radioactivity was recovered from adipose tissue of refed than fasted rats and from insulin treated than insulin deprived diabetic rats. Adipose tissue uptake of label appeared to be potentiated by insulin in normal as well as in diabetic rats. No definite differences in the rate of clearing chylomicrons from blood was noted in insulin treated and insulin deprived diabetic rats. Although the enhanced adipose tissue uptake of triglyceride fatty acid might be related to the availability of α glycerophosphate for esterification it is equally possible that adipose tissue lipoprotein lipase content may be a regulating factor. Heparin, as opposed to saline administration prior to chyle injection, produced marked acceleration in the rate of removal of chyle from the blood of treated and untreated diabetic animals. The accelerated removal was related to accelerated uptake of activity by the liver and could be attributed in part to intravascular lipolysis of chyle triglyceride. The effect of heparin on the degree and the nature of hepatic uptake was no different in treated and untreated diabetic animals

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03163.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractEvoked potentials from contralateral hindlimb nerves were recorded in SIand SIIof cats anesthetized with Nembutal. Initially positive short latency potentials could be elicited from low threshold cutaneous afferents and low (groups I and II) and high (group III) threshold muscle afferents as well as high threshold afferents of the posterior knee‐joint nerve. The low threshold muscle afferents were not of stretch receptor origin. The effects were transmitted via two spinal pathways, the dorsal columns and the spinocervical tract. The transmission via the spinocervical tract was faster by 2 msec for cutaneous impulses and by 7 msec for impulses from group III muscle afferents. The finding of McIntyre (1962b) that the low threshold afferents of the interosseous nerve project mainly to SIIvia the dorsal columns was confirmed. After transection of the above‐mentioned pathways, initially negative short latency potentials could be elicited from low threshold cutaneous afferents and high threshold muscle afferents via a pathway in the ventral quadrant contralateral to the stimulated ner

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03164.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractThe effect of 19 metabolic and ion transport inhibitors acting at various enzymatic levels within several metabolic pathways was investigated upon a single neurone preparation of the crayfish stretch receptor organ. Both the nerve cell function as judged by its impulse activity and its metabolism expressed by oxygen uptake were studied. Each inhibitor was tried at various concentrations and pH values. The effect of the respiratory inhibitors, especially rotenone and antimycin A, suggests a coupling of respiration and impulse activity in the crustacean nerve cell. The marked effect of the glycolytic inhibitors and of Na‐malonate strongly suggests a link between glycolysis and Krebs' cycle from one side and maintenance of impulse activity from the other. This view is also supported by the effect of glucose restoring activity after the block caused by several inhibitors. Ouabain and digoxin inhibit both impulse activity and oxygen uptake. In general respiration seems to be less sensitive to inhibitors than the impulse activity, indicating the presence of a safety factor for respiratory processe

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03165.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractThe level of several glycolytic intermediates, phosphate compounds, and reduced and oxidized pyridine nucleotides was determined in an isolated crustacean nerve cell preparation both at rest and after prolonged physiological stimulation. The glycogen decreased consistently with the lactate increase during impulse activity. ATP showed a continuous decrease during prolonged stimulation while ADP and Pi showed opposite patterns. After stimulation, the ratio TPN/TPNH fell by more than 50 per cent. This was due to a decrease of TPN. Similarly, the DPN/DPNH ratio fell by 50 per cent, but in this case it was due to a decrease of DPN and a simultaneous increase of DPNH. The results strongly suggest the involvement of glycolysis in the mechanism maintaining impulse activity in this neurone. Impulse activity in the crustacean nerve cell is linked to an energy requiring system. This energy is furnished by ATP splitting and glycolysis directly or through the arginine phosphate step supporting the ATP resynthesis.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03166.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractThe effect of seven intermediates of the TCA cycle, of pyruvate and glutamate, was studied on the impulse activity and oxygen uptake of the slowly adapting cell of the stretch receptor organ of crayfish. Citrate, isocitrate, α‐ketoglutarate and succinate showed a strong excitatory action, fumarate, malate, oxaloacetate and pyruvate had no action while glutamate had an inhibitory action on the impulse activity. The most effective substrate tested was citrate which also increased respiration sevenfold. Isocitrate showed a lower effect (2.2 fold) as did α‐ketoglutarate (4 fold), succinate (2.8 fold) and malate (3 fold). Fumarate, pyruvate and glutamate did not have any effect on the respiratory activity. The only substrate showing an inhibitory effect on oxygen uptake was oxaloacetate. Glucose, tested for comparison, also showed stimulatory effect (2.4 fold) on respiration. The authors are inclined to believe that the effect on the impusle activity and respiration exerted by these compounds is confined to the nerve cell membrane. The opposite modes of action of malate and oxaloacetate on respiration, which did not affect impulse activity, are however more difficult to explain in terms of a pure membrane mech

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03167.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractOn the infusion of 11.5 mg L(+)lactate per kg per min for 60 min in the rabbit the increase in the lactate concentration in the blood was smaller in thyroxine‐treated than in untreated and thyroidectomized animals. This was considered to be due to an increase in the metabolic rate of lactate after thyroxine. The regression coefficient for the correlation between the stimulation of oxygen consumption and the increase in the lactic acid content of the blood was higher in thyroxine‐treated than in untreated and thyroidectomized anim

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03168.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractParasympathetic and sympathetic influence on the“tone” of the bladder was revealed through alterations in the slope of the pressure‐volume records (cystometrograms) following partial and complete section of the autonomic nerve supplies to the vesical wall. When all bladder nerves but the efferent parasympathetic fibres were cut bilaterally, a marked elevation of vesical tone was noted. By additional section of the efferent parasympathetic supply (total extrinsic denervation) this increase in the tone of the bladder was completely abolished. A moderate decrease in vesical tone primarily ensued by section of the parasympathetic supply alone, leaving the sympathetic innervation intact. After additional sympathetic denervation, thereby depriving the bladder of all extrinsic nerves, vesical tone again increased close up to normal levels. Thus, the tone of the urinary bladder was shown to be under influence of excitatory parasympathetic and inhibitory sympathetic ef

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03169.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractThe micturition act was found to be regulated by an antagonistic nervous influence mediated through the two peripheral autonomic pathways to the bladder. The alterations of micturition following section and stimulation of these nerves were recorded by means of a technique (Gjone and Setekleiv 1963, Gjone 1965a, b) which does not interfere with the emptying function of the bladder. By section of theparasympatheticvesical supply the micturition reflex was abolished, whereas micturition was induced by parasympathetic stimulation. In accordance with the results of previous workers,excitatoryeffects on micturition were thus found to be mediated by this pathway. Following primary section of thesympatheticnerves the micturition threshold was markedly reduced, and by sympathetic stimulation interruption of reflex micturition ensued. By the latter effect, not previously demonstrated, theinhibitoryinfluence of the sympathetic nerves to the bladder, was established. The activity of the so called“internal sphincter” was studied through direct cystoscopic examination as well as by pressure recording from the outlet region. It was concluded that the smooth muscle surrounding the internal urethral orifice acts in phase with and as part of the detrusor musculature,viz.,the closure of the bladder outlet is due to relaxation, and its opening is caused by contraction. In support of this view it was noted that urinary continence persisted when the musculature of 1 he bladder neck was divided by a vertical incision, whereas incomplete and prolonged emptying of the bladder ensued subsequent to this proced

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03170.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY

摘要:

AbstractBy means of intravesical pressure recording through a cystostomy, supraspinal influence on the urinary bladder was studied by stereotaxic stimulation of the cat's brain. The separation of excitatory and inhibitory brain loci was in this work based on the different effects upon the micturition reflex only. Excitatory responses to stimulation were identified by induction of micturition, and inhibition by interruption of a micturition act initiated by rapid filling of the bladder. The following new findings are reported: Within the amygdaloid nuclear complex and the pyriform cortex excitatory bladder responses were obtained on stimulation of the basolateral division, and inhibition on stimulation of the corticomedial area. By hypothalamic stimulation a dorsolateral excitatory and a ventromedial inhibitory field was found. Inhibitory bladder responses were demonstrated from the posterior cingulate gyrus and from the reticular formation of the upper brain stem. Predominantly excitatory responses were produced by stimulation of the superior collicule and from the periaquaeductal grey substance. Excitatory responses from all these regions were abolished by section of the parasympathetic bladder supply, but remained unaltered by sympathetic denervation. Inhibitory responses were abolished when the sympathetic bladder supply was cut. Thus, excitatory effects of stimulation were identified as parasympathetic and inhibitory effects as sympathetic in nature.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1966.tb03171.x

出版商:Blackwell Publishing Ltd    

年代:1966

数据来源: WILEY