摘要:

AbstractEndometrial blood flow (EBF) was studied atraumatically in guinea‐pigs by the133xenon clearance technique. With the aid of an otoscope, a xenon‐saline solution was deposited via the vagina through a cannula into the uterine lumen. Radioactivity curves were obtained by a small external scintillation detector. Oophorectorny lowered total flow whereas this was markedly increased (also per unit weight) by estrogen treatment, alone or in combination with oophorectomy. During early pregnancy there was a tendency to increase in the flow, while the values (for the parietal decidua) were markedly reduced at later stages of pregnancy. In the fetus‐placenta unit (133xenon solution injected intra‐amniotically) the flow was three times higher than in the parietal decidua at this advanced stage of pr

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1975.tb05794.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractThe effects of K+, Na+, hypo‐ and hypertonicity on the synthesis and fast axonal transport of3H‐leucine‐labelled protein were studiedin vitroin the frog sciatic system. The methodology used made it possible to discriminate between effects on synthesis and transport of protein. The preparation which consisted of the dorsal ganglia, the sciatic nerve and the gastrocnemius muscle was placed in an incubation chamber. The ganglia were incubated in standard Ringer containingSH‐leucine and the nerve was prefused with modified Ringer. Perfusion of the nerve for 17 h with K+‐free Ringer or Na+‐free Ringer did not affect the rapid axonal transport of3H‐leucine‐labelled material from the ganglia along the nerve towards a ligature in front of which it accumulated. Nor was the transport influenced by concentrations of K+up to 68.8 mM. In contrast concentrations exceeding 100 mM K+partially inhibited the transport. Inhibition by ouabain (0.1 mM) was not prevented by elevating K+to 30 mM. Deviation from isotonicity, towards a hypo‐ or a hypertonic medium, partially inhibited axonal transport. The transport inhibitory effects showed reversibility. Experimental conditions, which arrested the transport, were tested in separate experiments for effects on uptake of3H‐leucine into TCA‐soluble and insoluble ganglionic components. K+substituted for Na+, ouabain (0.1 mM) and hypotonic Ringer partially inhibited the amino acid uptake hut also subsequent steps in the incorporation process, whereas only the latter was inhibited by hypertonic Ringer. The results are discussed in relation to possible changes

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1975.tb05795.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractIn order to test the hypothesis that ACh mediates the transmission of pain stimuli from dentin to sensory intradental nerve endings the following experiments were performed.Intradental nerve impulses were recorded by means of low impedance electrodes inserted in dentinal cavities in the tooth of the cat. An air blast proved to be an efficient physical stimulus to excite the intradental nerves. Local application of acetylcholine caused a similar response. This response to acetylcholine was followed by a transient blockage to repeated application. The response to acetylcholine could be blocked by d‐tubocurarine, atropine, succinylcholine and hexamethonium administered locally. In contrast, the response to physical stimuli (air blasts) could not be blocked by these drugs. Moreover, during the period of depression following acetylcholine the preparation responded to physical stimuli. These findings suggest that acetylcholine is not a mediator in the intradental pain transmission provoked by physical stimul

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1975.tb05796.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractExtracellular microelectrode recordings were made in the forelimb and/or hindlimb areas of the cerebral post‐central gyri of 7 monkeys before and/or after acute dorsal hemisections of the cervical or low thoracic spinal cord. The animals were anaesthetized with either pentobarbitone sodium or chloralose. Among the units which were encountered after the lesions were 114 which could be influenced from the periphery. 38 units discharged to light tactile stimulation of small receptive fields and had a topographical organization like that observed in the intact animal. The remaining 76 units could be activated by peripheral electrical stimulation and/or by tapping, squeezing or light pinching. No units were found which specifically were activated by noxious stimuli. The two groups of cortical units responded with latencies only slightly longer than those obtained in the intact preparation. In the light of previous findings these electrophysio‐logical data suggest that, unlike carnivora, primates may possess the ventral spinal somatosensory pathway traditionally postulated on the basis of neurological mater

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1975.tb05797.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractThe effects of moderate arterial hyperosmolality (+ 20 mOsm/kg H2O), produced by short term intravenous hypertonic infusion, on vascular resistance in skin, skeletal muscle, intestine, and kidney were analysed in the anesthetized cat. Vascular resistance decreased in all four regions in response to the hypertonicity both before and after regional sympathectomy and the effects were not significantly altered by β‐adrcno‐ceptor blockade. Arterial blood pressure rose during the hypertonic infusion despite the decreased vascular resistance and an unchanged heart rate, indicating an increased stroke volume and cardiac output. Similar increases of arterial osmolality are known to occur in heavy exercise and in hemorrhage. The present results may therefore suggest that blood borne hyperosmolality is a factor which can contribute to the overall cardiovascular adjustments in these situat

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1975.tb05798.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

AbstractRelationship between isometric endurance performance at 50% of maximal voluntary isometric contraction (MVC) and skeletal muscle fibre composition has been elucidated in 19 physical education students. This was found to be linear and the equation corresponded to:y=9.35 + 1.093x;r= 0.70 (endurance time expressed in seconds and fibre composition as percent slow twitch muscle fibres (ST) of the vastus lateralis muscle). As it is assumed from previous studies that similar isometric tensions preferentially recruit fast twitch muscle fibres (FT) and that the muscle at the point of exhaustion exhibits maximal values for lactate accumulation, it is suggested that lactate formed in FT fibres is released and stored in nonrecruited ST fibres. The ability to sustain similar isometric tension would then be depending on how large the fraction of ST fibres is that can serve as a lactate recipient for lactate producing FT fibres.

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1975.tb05799.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1975.tb05800.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

ISSN:0001-6772    

DOI:10.1111/j.1748-1716.1975.tb05801.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY