Transmural Nerve Stimulation of Blood Vessels in vitro: a Critical Examination

1980 ◽  
Vol 17 (1) ◽  
pp. 53-57
Author(s):  
Sue Piper Duckles ◽  
Robert W. Silverman
Keyword(s):  
Blood Vessels ◽  
Nerve Stimulation ◽  
Critical Examination ◽  
Stimulation Of

Comparative Physiology of the Vertebrate Autonomic Nervous System

1963 ◽  
Vol 40 (3) ◽  
pp. 421-436
Author(s):  
G. BURNSTOCK ◽  
G. CAMPBELL
Keyword(s):  
Nerve Stimulation ◽  
Histological Study ◽  
Circular Muscle ◽  
Vascular Supply ◽  
Evolutionary Significance ◽  
Blocking Agents ◽  
Pelvic Nerves ◽  
Drug Actions ◽  
Stimulation Of

1. A histological study of the structure of the urinary bladder of the ringtail possum has been made. The innervation of the bladder has been studied in vitro, using the technique of analytical pharmacology. 2. The bladder has well-defined inner longitudinal and outer circular muscle layers. Nerves supplying the bladder are found both in the pelvic nerves and in the vesical nerves which run with the vascular supply of the bladder fundus. Ganglia have been demonstrated along the trunks of the vesical nerves and also aggregated at the bladder neck. 3. The response of the bladder to stimulation of either nerve supply in situ or in vitro is always a simultaneous contraction of both longitudinal and circular muscles. Inhibitory responses to nerve stimulation have never been observed. The optimal frequency for stimulation of these nerves at 30° C. is 50 pulses/sec. 4. The bladder is contracted by ACh and 5-hydroxytryptamine, but is relaxed by adrenaline, noradrenaline and histamine. 5. The response to nerve stimulation is reduced by atropine and potentiated by eserine. Adrenergic blocking agents do not affect the nerve-mediated response unless they also affect the response to applied ACh in a similar manner. 6. Ganglionic blocking agents, in concentrations which do not reduce the response to ACh, cause up to a 40% reduction of the response to stimulation of either the vesical or the pelvic nerves. 7. It is concluded that the nerve fibres supplying the possum bladder are cholinergic, perhaps 40 % of them being stimulated pre-ganglionically. 8. The evolutionary significance of these observations is discussed. 9. Some points of pharmacological interest have been discussed in relation to drug actions on placental mammal preparations.

Neuromuscular control of the glottis in a primitive air-breathing fish, Amia calva

1993 ◽  
Vol 264 (1) ◽  
pp. R204-R210
Author(s):  
P. J. Davies ◽  
M. S. Hedrick ◽  
D. R. Jones
Keyword(s):  
Skeletal Muscle ◽  
Smooth Muscle ◽  
Nerve Stimulation ◽  
Muscle Tension ◽  
Neuromuscular Control ◽  
Isometric Tension ◽  
Direct Stimulation ◽  
Amia Calva ◽  
Stimulation Of

The neuromuscular control of the glottis, a muscular sphincter that controls air flow to and from the swim bladder, was investigated using in vitro preparations from bowfin (Amia calva). Stimulation of the ramus intestinalis branch of the vagus nerve caused an increase in isometric tension of the glottal musculature, indicating active closure. The glottis could be actively opened only by direct stimulation of muscle bundles lying lateral to the glottis. In 19 of 24 preparations supramaximal nerve stimulation (20 Hz, 10 V) caused a two-phase increase in muscle tension. Immediately after the onset of stimulation there was a rapid increase in muscle tension. After the end of the train of stimuli, the tension decreased and then again increased briefly followed by a slow return to baseline lasting approximately 60 s. The addition of hyoscine reduced maximum tension of the response by 63 +/- 7% and abolished the second slower element of the response to vagal stimulation. The remaining faster response to nerve stimulation was abolished by tubocurarine. Applied acetylcholine or carbachol mimicked the slow response, causing a slow-onset sustained contraction that was abolished by hyoscine. Hence, the musculature showed physiological characteristics of both skeletal and smooth muscle. Histological examination of the glottis confirmed the physiological results: smooth muscle fibers were found lining the pneumatic duct and lumen of the glottis arranged in a circular fashion around the lateral margins of the glottis. Distinct skeletal muscle bundles were found lateral to the smooth muscle and also arranged in parallel with the glottal lumen, forming a skeletal muscle sphincter.(ABSTRACT TRUNCATED AT 250 WORDS)

Differential effects of pinacidil and cromakalim on vascular relaxation and sympathetic neurotransmission

1994 ◽  
Vol 72 (7) ◽  
pp. 801-810 ◽  
Author(s):  
Baiqiang Cai ◽  
Qinzhong Hao ◽  
Stan S. Greenberg ◽  
Bennett deBoisblanc ◽  
Doug Gillott ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Blood Vessels ◽  
Nerve Stimulation ◽  
Mesenteric Artery ◽  
Tension Development ◽  
Voltage Dependent ◽  
Prostaglandin F ◽  
Synaptic Responses

We tested the hypothesis that pinacidil and cromakalim acted at different sites to relax vascular smooth muscle, in vitro. We compared the effects of pinacidil and cromakalim on tension development in isolated canine and bovine pulmonary artery and vein and canine mesenteric artery and dorsal metatarsal vein, and on the pre- and post-synaptic responses of the canine blood vessels to transmural nerve stimulation. Both pinacidil and cromakalim relaxed bovine and canine blood vessels precontracted to 50% of maximal tension with U46619, prostaglandin F2α, or norepinephrine. Pinacidil- and cromaklim-mediated relaxations of the blood vessels were not mediated by endothelium-derived factors, prostanoids, muscarinic receptors, β-adrenoceptors, or Ca2+-activated or voltage-dependent K+ channels, since they were unaffected by endothelium-rubbing, indomethacin, L-NG-monomethyl-L-arginine, atropine, propranolol, and charybdotoxin. Glibenchlamide, an inhibitor of ATP-activated K+ channels (K+ATP), and KCl (25–60 mM) sufficient to minimize the role of K+ channels almost abolished cromakalim- but not pinacidil-induced relaxation of the blood vessels. Pinacidil inhibited the contractions of the dorsal metatarsal vein and mesenteric artery to norepinephrine and transmural nerve stimulation and the efflux of 2-[14C]norepinephrine during transmural nerve stimulation. In contrast, 1 and 10 nM cromakalim enhanced while 0.1 and 1 μM cromakalim inhibited the contractions of, and 2-[14C]norepinephrine efflux from, the mesenteric artery and dorsal metatarsal vein during transmural nerve stimulation. Thus, pinacidil and cromakalim relax smooth muscle by stimulation of K+ATP channels. Pinacidil also relaxes the blood vessels by a K+ channel independent mechanism. Pinacidil-induced relaxation may also result from presynaptic inhibition of norepinephrine release from the sympathetic neuron.Key words: potassium channels, pulmonary blood vessels, systemic blood vessels, glibenclamide, pinacidil, cromakalim, neurotransmission.

scholarly journals Wireless endovascular nerve stimulation with a millimeter-sized magnetoelectric implant

2021 ◽  
Author(s):  
Joshua C Chen ◽  
Peter Kan ◽  
Zhanghao Yu ◽  
Fatima Alrashdan ◽  
Roberto Garcia ◽  
...  
Keyword(s):  
Blood Vessels ◽  
Nerve Stimulation ◽  
Peripheral Nerves ◽  
Pulse Generators ◽  
Percutaneous Catheter ◽  
Digitally Programmable ◽  
Magnetoelectric Materials ◽  
System On A Chip ◽  
Barrier To Entry ◽  
Stimulation Of

Implanted bioelectronic devices have the potential to treat disorders that are resistant to traditional pharmacological therapies; however, reaching many therapeutic nerve targets requires invasive surgeries and implantation of centimeter-sized devices. Here we show that it is possible to stimulate peripheral nerves from within blood vessels using a millimeter-sized wireless implant. By directing the stimulating leads through the blood vessels we can target specific nerves that are difficult to reach with traditional surgeries. Furthermore, we demonstrate this endovascular nerve stimulation (EVNS) with a millimeter sized wireless stimulator that can be delivered minimally invasively through a percutaneous catheter which would significantly lower the barrier to entry for neuromodulatory treatment approaches because of the reduced risk. This miniaturization is achieved by using magnetoelectric materials to efficiently deliver data and power through tissue to a digitally-programmable 0.8 mm2 CMOS system-on-a-chip. As a proof-of-principle we show wireless stimulation of peripheral nerve targets both directly and from within the blood vessels in rodent and porcine models. The wireless EVNS concept described here provides a path toward minimally invasive bioelectronics where mm-sized implants combined with endovascular stimulation enable access to a number of nerve targets without open surgery or implantation of battery-powered pulse generators.

Persistence of Fibrinolytic Activity in Fragments of Human Veins Cultured in Vitro

1970 ◽  
Vol 24 (01/02) ◽  
pp. 043-047 ◽  
Author(s):  
M Pandolfi
Keyword(s):  
Blood Vessels ◽  
Plasminogen Activator ◽  
Fibrinolytic Activity ◽  
Vasa Vasorum ◽  
Adult Human ◽  
Slide Technique

SummaryExplants from 5 adult human veins were cultured in a fibrinolytically inactive medium for 3 weeks and assayed for the presence of plasminogen activator by the fibrin slide technique. The explants from 3 veins showed fibrinolytic activity confined to their vasa vasorum for the whole duration of the culture; no decrease of activity was seen. The finding suggests that small blood vessels are able to synthesize plasminogen activator.

Early Platelet-Collagen Interactions in Whole Blood and Their Modifications by Aspirin and Dipyridamole Evaluated by a New Method (Basic Wave)

1985 ◽  
Vol 54 (04) ◽  
pp. 799-803 ◽  
Author(s):  
José Luís Pérez-Requejo ◽  
Justo Aznar ◽  
M Teresa Santos ◽  
Juana Vallés
Keyword(s):  
Whole Blood ◽  
Ex Vivo ◽  
Platelet Rich Plasma ◽  
White Blood Cells ◽  
Reversible Aggregation ◽  
Inhibitory Compounds ◽  
Rapid Generation ◽  
Stimulation Of ◽  
Collagen Stimulation

SummaryIt is shown that the supernatant of unstirred whole blood at 37° C, stimulated by 1 μg/ml of collagen for 10 sec, produces a rapid generation of pro and antiaggregatory compounds with a final proaggregatory activity which can be detected for more than 60 min on a platelet rich plasma (PRP) by turbidometric aggregometry. A reversible aggregation wave that we have called BASIC wave (for Blood Aggregation Stimulatory and Inhibitory Compounds) is recorded. The collagen stimulation of unstirred PRP produces a similar but smaller BASIC wave. BASIC’s intensity increases if erythrocytes are added to PRP but decreases if white blood cells are added instead. Aspirin abolishes “ex vivo” the ability of whole blood and PRP to generate BASIC waves and dipyridamole “in vitro” significantly reduces BASIC’s intensity in whole blood in every tested sample, but shows little effect in PRP.

DER EINFLUSS VON RESERPIN AUF DIE ANTITHYREOIDALE WIRKUNG VON KALIUMPERCHLORAT

1962 ◽  
Vol 39 (3) ◽  
pp. 423-430
Author(s):  
H. L. Krüskemper ◽  
F. J. Kessler ◽  
E. Steinkrüger
Keyword(s):  
Thyroid Gland ◽  
Male Rats ◽  
Normal Male ◽  
Tissue Respiration ◽  
List Type ◽  
Morphological Alterations ◽  
Hormone Synthesis ◽  
Stimulation Of

ABSTRACT 1. Reserpine does not inhibit the tissue respiration of liver in normal male rats (in vitro). 2. The decrease of tissue respiration of the liver with simultaneous morphological stimulation of the thyroid gland after long administration of reserpine is due to a minute inhibition of the hormone synthesis in the thyroid gland. 3. The morphological alterations of the thyroid in experimental hypothyroidism due to perchlorate can not be prevented with reserpine.

EFFECT OF ACTINOMYCIN D ON TSH-INDUCED STIMULATION OF THYROIDAL PROTEIN SYNTHESIS IN THE RAT

1974 ◽  
Vol 77 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Gustav Wägar
Keyword(s):  
Protein Synthesis ◽  
Actinomycin D ◽  
The Other ◽  
Leucine Incorporation ◽  
Short Term ◽  
Other Hand ◽  
Thyroid Glands ◽  
Translational Level ◽  
Stimulation Of

ABSTRACT Whether the short-term regulation of thyroidal protein synthesis by TSH occurs at the transcriptional or the translational level was tested by measuring the effect of actinomycin D (act D) on the TSH-induced stimulation of L-14C-leucine incorporation into the thyroidal proteins of rats. TSH was injected 6 h before the rats were killed. The thyroid glands were then removed and incubated in vitro in the presence of L-14C-leucine for 2 h. The pronounced stimulation of leucine incorporation in the TSH-treated animals was depressed as compared with controls but still significant even when the animals had been pre-treated with 100 μg act D 24 and 7 h before sacrifice. On the other hand, act D strongly decreased incorporation of 3H-uridine into RNA. Short-term regulation of thyroidal protein synthesis by TSH appears to be partly but not wholly dependent on neosynthesis of RNA. Hence regulation may partly occur at the translation level of protein synthesis.

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