Routine hypercapnic challenge after cervical spinal hemisection affects the size of phrenic motoneurons
Abstract After an individual experiences a cervical cord injury, the cell body's adaptation to the smaller size of phrenic motoneurons occurs within several weeks. It is not known whether a routine hypercapnic load can alter this adaptation of phrenic motoneurons. We investigated this question...
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| Format: | Article |
| Language: | English |
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Nature Portfolio
2023-08-01
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| Series: | Scientific Reports |
| Online Access: | https://doi.org/10.1038/s41598-023-40505-x |
| _version_ | 1797452691123732480 |
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| author | Kenta Kawamura Masaaki Kobayashi Kazuhide Tomita |
| author_facet | Kenta Kawamura Masaaki Kobayashi Kazuhide Tomita |
| author_sort | Kenta Kawamura |
| collection | DOAJ |
| description | Abstract After an individual experiences a cervical cord injury, the cell body's adaptation to the smaller size of phrenic motoneurons occurs within several weeks. It is not known whether a routine hypercapnic load can alter this adaptation of phrenic motoneurons. We investigated this question by using rats with high cervical cord hemisection. The rats were divided into four groups: control, hypercapnia, sham, and sham hypercapnia. Within 72 h post-hemisection, the hypercapnia groups began a hypercapnic challenge (20 min/day, 4 times/week for 3 weeks) with 7% CO2 under awake conditions. After the 3-week challenge, the phrenic motoneurons in all of the rats were retrogradely labeled with horseradish peroxidase, and the motoneuron sizes in each group were compared. The average diameter, cross-sectional area, and somal surface area of stained phrenic motoneurons as analyzed by software were significantly smaller in only the control group compared to the other groups. The histogram distribution was unimodal, with larger between-group size differences for motoneurons in the horizontal plane than in the transverse plane. Our findings indicate that a routine hypercapnic challenge may increase the input to phrenic motoneurons and alter the propensity for motoneuron adaptations. |
| first_indexed | 2024-03-09T15:12:18Z |
| format | Article |
| id | doaj.art-f9a75e9f2bda457eb2876d9c67b34ced |
| institution | Directory Open Access Journal |
| issn | 2045-2322 |
| language | English |
| last_indexed | 2024-03-09T15:12:18Z |
| publishDate | 2023-08-01 |
| publisher | Nature Portfolio |
| record_format | Article |
| series | Scientific Reports |
| spelling | doaj.art-f9a75e9f2bda457eb2876d9c67b34ced2023-11-26T13:19:38ZengNature PortfolioScientific Reports2045-23222023-08-011311810.1038/s41598-023-40505-xRoutine hypercapnic challenge after cervical spinal hemisection affects the size of phrenic motoneuronsKenta Kawamura0Masaaki Kobayashi1Kazuhide Tomita2Department of Physical Therapy, Ibaraki Prefectural University of Health SciencesGraduate School of Health Science, Ibaraki Prefectural University of Health SciencesDepartment of Physical Therapy, Ibaraki Prefectural University of Health SciencesAbstract After an individual experiences a cervical cord injury, the cell body's adaptation to the smaller size of phrenic motoneurons occurs within several weeks. It is not known whether a routine hypercapnic load can alter this adaptation of phrenic motoneurons. We investigated this question by using rats with high cervical cord hemisection. The rats were divided into four groups: control, hypercapnia, sham, and sham hypercapnia. Within 72 h post-hemisection, the hypercapnia groups began a hypercapnic challenge (20 min/day, 4 times/week for 3 weeks) with 7% CO2 under awake conditions. After the 3-week challenge, the phrenic motoneurons in all of the rats were retrogradely labeled with horseradish peroxidase, and the motoneuron sizes in each group were compared. The average diameter, cross-sectional area, and somal surface area of stained phrenic motoneurons as analyzed by software were significantly smaller in only the control group compared to the other groups. The histogram distribution was unimodal, with larger between-group size differences for motoneurons in the horizontal plane than in the transverse plane. Our findings indicate that a routine hypercapnic challenge may increase the input to phrenic motoneurons and alter the propensity for motoneuron adaptations.https://doi.org/10.1038/s41598-023-40505-x |
| spellingShingle | Kenta Kawamura Masaaki Kobayashi Kazuhide Tomita Routine hypercapnic challenge after cervical spinal hemisection affects the size of phrenic motoneurons Scientific Reports |
| title | Routine hypercapnic challenge after cervical spinal hemisection affects the size of phrenic motoneurons |
| title_full | Routine hypercapnic challenge after cervical spinal hemisection affects the size of phrenic motoneurons |
| title_fullStr | Routine hypercapnic challenge after cervical spinal hemisection affects the size of phrenic motoneurons |
| title_full_unstemmed | Routine hypercapnic challenge after cervical spinal hemisection affects the size of phrenic motoneurons |
| title_short | Routine hypercapnic challenge after cervical spinal hemisection affects the size of phrenic motoneurons |
| title_sort | routine hypercapnic challenge after cervical spinal hemisection affects the size of phrenic motoneurons |
| url | https://doi.org/10.1038/s41598-023-40505-x |
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