摘要:

The dorsal and ventral vertebral muscles of the back and tail of the albino Norway rat are described and discussed. These muscles were analyzed because they are undoubtably used during the sexual posturing, lordosis, of the female rat, as well as participating in a variety of other behaviors.The muscles are described by region (thoracic-lumbar or sacrocaudal), and the classifications of Vallois are followed where possible. Of the epaxial (dorsal) muscles, the three longitudinal systems of muscles, the transversospinalis, the longissimus, and the iliocostalis systems, can be identified in the albino rat. Muscles of the transversospinalis system are fused in the lumbar region, distinct and specialized in the thoracic region, and form the tail muscle extensor caudae medialis caudally. The iliocostalis system of the lumbar region is fused with one component of the lumbar longissimus system to form lateral longissimus. Anteriorly, iliocostalis thoracis and cervicis represent the iliocostalis system. The lumbar longissimus system is represented by the longissimus component of lateral longissimus, medial longissimus, and a short-fiber component. Longissimus dorsi is the anterior continuation of the longissimus portion of the lateral longissimus. The short-fiber component also continues into the thoracic region, where it becomes difficult to separate out from longissimus dorsi. Medial longissimus represents the excursion into the lumbar region of the long, tendinous, tailbase-tail muscle, longissimus caudae; the caudal portion of this muscle is extensor caudae lateralis. The remaining dorsal muscle described is the tail muscle, abductor caudae dorsalis.The hyposomal (ventral) muscles described are quadratus lumborum and the intertransversarii, present in the lumbar region; the muscles iliococcygeus, pubococ-cygeus and coccygeus which arise from the medial face of the pelvis and insert onto the proximal tail; the long, tendinous, tail muscles, flexor caudae brevisi and longus; and the ventral and lateral set of segmental tail muscles.The innervation of the lumbar transversospinalis muscles by the medial branches and of lateral longissimus by the lateral branches of the dorsal rami of the spinal nerves was traced and confirmed by electrical stimulation of the nerve branches. The innervation of medial longissimus is also described. Additionally, movements of the vertebral column produced by direct unilateral or bilateral muscle stimulation were observed for a number of the muscles.

ISSN:0006-8977    

DOI:10.1159/000121788

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

The dorsal and ventral vertebral muscles of the back and tail of the albino Norway rat are described and discussed. These muscles were analyzed because they are undoubtably used during the sexual posturing, lordosis, of the female rat, as well as participating in a variety of other behaviors.The muscles are described by region (thoracic-lumbar or sacrocaudal), and the classifications of Vallois are followed where possible. Of the epaxial (dorsal) muscles, the three longitudinal systems of muscles, the transversospinalis, the longissimus, and the iliocostalis systems, can be identified in the albino rat. Muscles of the transversospinalis system are fused in the lumbar region, distinct and specialized in the thoracic region, and form the tail muscle extensor caudae medialis caudally. The iliocostalis system of the lumbar region is fused with one component of the lumbar longissimus system to form lateral longissimus. Anteriorly, iliocostalis thoracis and cervicis represent the iliocostalis system. The lumbar longissimus system is represented by the longissimus component of lateral longissimus, medial longissimus, and a short-fiber component. Longissimus dorsi is the anterior continuation of the longissimus portion of the lateral longissimus. The short-fiber component also continues into the thoracic region, where it becomes difficult to separate out from longissimus dorsi. Medial longissimus represents the excursion into the lumbar region of the long, tendinous, tailbase-tail muscle, longissimus caudae; the caudal portion of this muscle is extensor caudae lateralis. The remaining dorsal muscle described is the tail muscle, abductor caudae dorsalis.The hyposomal (ventral) muscles described are quadratus lumborum and the intertransversarii, present in the lumbar region; the muscles iliococcygeus, pubococ-cygeus and coccygeus which arise from the medial face of the pelvis and insert onto the proximal tail; the long, tendinous, tail muscles, flexor caudae brevisi and longus; and the ventral and lateral set of segmental tail muscles.The innervation of the lumbar transversospinalis muscles by the medial branches and of lateral longissimus by the lateral branches of the dorsal rami of the spinal nerves was traced and confirmed by electrical stimulation of the nerve branches. The innervation of medial longissimus is also described. Additionally, movements of the vertebral column produced by direct unilateral or bilateral muscle stimulation were observed for a number of the muscles.

ISSN:0006-8977    

DOI:10.1159/000121789

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

Male Puerto Rican treefrogs, Eleutherodactylus coqui, produce a two-note call: a 100-msec constant frequency ''Co'' note, followed by a longer, upward sweeping ''Qui'' note. Previous behavioral studies have shown that males respond selectively to natural and synthetic call notes of 100 msec duration, whereas preliminary results suggest that females respond preferentially to the second note in the male''s call. In the present study, we first show that the basilar papilla in the inner ear is tuned differently in males and females. Comparisons were next made between cells in the eighth nerve and midbrain torus semicircularis of firing rate vs. duration functions in order to help determine the underlying neural mechanisms responsible for the behavioral selectivity to notes of 100 msec duration. A model for detection of vocalizations of specific durations is postulated and discussed in the light of the observed calling behavior of the male as well as the response properties of a class of cells found in the torus semicircularis.

ISSN:0006-8977    

DOI:10.1159/000121790

出版商:S. Karger AG    

年代:1980

数据来源: Karger

摘要:

Ablations of lateral longissimus, medial longissimus, and the lumbar transversospinalis system were performed singly and sequentially on female albino rats. Animals were tested postoperatively with males and by manual stimulation for lordosis. In tests with males, the strength of lordosis was rated specifically with respect to the extent of rump elevation; in manual stimulation tests, rating was based on the full lordotic response. Animals were also tested for the ability to cross a balance beam as an indication of the general status of the animals'' posture and locomotion. The data from tests with males proved more sensitive in showing up effects of the ablations on lordosis. Lateral longissimus ablations and transversospinalis ablations led predictably to worsened lordosis. Medial longissimus ablations did not significantly affect lordosis. The manual stimulation data were consistent with the data obtained in tests with males. Ablated animals were not impaired on the balance beam test. The results indicate that lateral longissimus and the lumbar transversospinalis system are major participants in the rump elevation of lordosis, an early and biologically important component of the lordotic response. This information permits focus on lateral longissimus and the lumbar transversospinalis system in the investigation of the neural control of lordosis.

ISSN:0006-8977    

DOI:10.1159/000121791

出版商:S. Karger AG    

年代:1980

数据来源: Karger