RESEARCH SUPPORT, U.S. GOV'T, P.H.S.
Add like
Add dislike
Add to saved papers

The organization of the motoneurons innervating the axial musculature of vertebrates. I. Goldfish (Carassius auratus) and mudpuppies (Necturus maculosus).

The motoneurons innervating different regions of the myomeres in goldfish and mudpuppies were examined by applying HRP to the musculature or to branches of spinal nerves. In goldfish, the populations of motoneurons innervating epaxial or hypaxial muscle occupied similar positions in the motor column and had similar size distributions. There was no relationship between the size or location of a motoneuron in the motor column and the dorsoventral location of the muscle it innervated in the myomeres. Instead, different populations of motoneurons innervated the functionally different red and white musculature. The red muscle was innervated only by small motoneurons that occupied the ventral portion of the motor column. Their small axons passed lateral to the Mauthner axon in the cord, and most of them traveled in a separate branch of each spinal nerve that ran in the horizontal septum to the red muscle. The white muscle was innervated by a population of motoneurons that did not innervate red. They were large and they occupied a characteristic position in the extreme dorsal part of the motor column. Their large axons traveled medial to the Mauthner axon in the cord and entered branches of spinal nerves running deep in the epaxial or hypaxial muscle. The white muscle was probably also innervated by some smaller motoneurons similar to those innervating red; however, these may have been motoneurons whose axons ran through white muscle to reach other muscle. The large motoneurons innervating only white muscle are similar to the primary motoneurons identified in developmental studies in teleosts (Myers: Soc. Neurosci. Abstr. 9:848, '83); the smaller ones, innervating both red and white, are like secondary motoneurons. Therefore, in goldfish, motoneurons having different morphology and developmental history also innervate different regions in the myomeres. The motor column in mudpuppies was, in general respects, similar to the column in goldfish. There were large primary motoneurons and small secondary ones. Though there were slight differences in the locations of motoneurons filled from nerves entering epaxial and hypaxial muscle, their distributions in the cord overlapped substantially. The motor columns in these two anamniotes differ substantially from the motor columns in those amniotes that have been studied. In amniotes, the motoneurons innervating epaxial and hypaxial muscles are spatially segregated in the cord (Smith and Hollyday: J. Comp. Neurol. 220:16-28, '83; Fetcho: J. Comp. Neurol. 249:551-563, '86).(ABSTRACT TRUNCATED AT 400 WORDS)

Full text links

For the best experience, use the Read mobile app

Group 7SearchHeart failure treatmentPapersTopicsCollectionsEffects of Sodium-Glucose Cotransporter 2 Inhibitors for the Treatment of Patients With Heart Failure Importance: Only 1 class of glucose-lowering agents-sodium-glucose cotransporter 2 (SGLT2) inhibitors-has been reported to decrease the risk of cardiovascular events primarily by reducingSeptember 1, 2017: JAMA CardiologyAssociations of albuminuria in patients with chronic heart failure: findings in the ALiskiren Observation of heart Failure Treatment study.CONCLUSIONS: Increased UACR is common in patients with heart failure, including non-diabetics. Urinary albumin creatininineJul, 2011: European Journal of Heart FailureRandomized Controlled TrialEffects of Liraglutide on Clinical Stability Among Patients With Advanced Heart Failure and Reduced Ejection Fraction: A Randomized Clinical Trial.Review

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app

Read by QxMD is copyright © 2021 QxMD Software Inc. All rights reserved. By using this service, you agree to our terms of use and privacy policy.

Get seemless 1-tap access through your institution/university

For the best experience, use the Read mobile app