Evidence map›Paper›PMID 32755357›Full record

ArticleJournal of neurophysiology2020

The neuromuscular transform in a single segment of a segmented heart tube.

Angela Wenning, Young Rim Chang, Brian J Norris, Ronald L Calabrese

Open access · bronzeAbstract read
In one paragraph

Article in Journal of neurophysiology, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact, top 92% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed, 1 citations in OpenAlex.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors at 1 institution in 1 country.

Angela WenningDepartment of Biology, Emory University, Atlanta, Georgia.ORCID 0000-0002-9400-6280
Young Rim ChangDepartment of Biology, Emory University, Atlanta, Georgia.ORCID 0000-0002-8723-9430
Brian J NorrisDepartment of Biology, Emory University, Atlanta, Georgia.
Ronald L CalabreseDepartment of Biology, Emory University, Atlanta, Georgia.ORCID 0000-0001-7135-3469
Emory University · US

Funding

Constancy and Variability in a Motor Program: CPG to Motor PerformanceR01NS085006 · NINDS · EMORY UNIVERSITY · PI CALABRESE, RONALD L · 2013 to 2016
$1.3M
HHS | NIH | National Institute of Neurological Disorders and Stroke (NINDS) R01 NS-085006NINDS NIH HHS R01 NS085006
6 · The paper itself

Abstract

Leech hearts are hybrids; they are myogenic but need entrainment by a heartbeat central pattern generator (CPG) to execute functional constriction patterns. Leech hearts are modular: two lateral segmented heart tubes running the length of the animal. Moving blood through the segmented heart tubes of leeches requires sequential constrictions, timed by a heartbeat CPG and relayed to each heart segment by likewise segmental motor neurons. The heartbeat CPG produces bilaterally asymmetric coordinations: rear-to-front peristaltic on one side and nearly synchronous on the other, periodically switching sides. We examined the neuromuscular transform of isolated heart segments in response to electrical nerve stimulation to identify the range of parameters (burst duration, intraburst pulse frequency, period) allowing the heart to constrict continuously and reliably. Constriction amplitudes increased with increasing intraburst frequencies and decreased with decreasing burst durations. Similar amplitudes were achieved with longer burst durations combined with lower frequencies or with shorter burst durations combined with higher frequencies. Long burst durations delayed relaxation, leading to summation and tetanus. The time, and its variability, between stimulus onset and time to constriction onset or to peak decreased with increasing frequency. Data previously obtained in vivo showed that the heart excitatory motor neurons fired longer bursts at lower frequencies at long periods moving to shorter bursts with higher intraburst frequencies as the period shortened. In this scenario, active constriction started earlier and the time to reach full systole shortened, allowing more time for relaxation. Relaxation time before the next motor neuron burst appears critical for maintaining constriction amplitude.

Indexed as

AnimalsCentral Pattern GeneratorsHeartLeechesMotor NeuronsMuscle Contractionleechmyogenicneurogenic heartneuromuscular transform

Identifiers

PMID32755357
PMCPMC7509300
OpenAlexW3047047072

What Socratic holds

Textmetadata
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.