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L C Hudson

Publications and source records attributed to L C Hudson.

10 recordsLinked to original sources
PubMed1992

Innervation of the feline eyelids.

The innervation of the eyelids is incompletely understood. This is a particular problem for those who wish to develop animal models of eyelid dysfunction in humans. Blepharospasm, for example, is a disease of uncontrolled eyelid spasm that is difficult to manage clinically because the aetiology is not understood. The anatomical literature on eyelid innervation is sparse and even conflicting. We attempted to study eyelid innervation, both sensory and motor, with injection of horseradish peroxidase (HRP) into the superior eyelid, inferior eyelid, and bulbar conjunctiva. We used 13 anesthetized weanling cats. Shape and structure of the facial nucleus varied along its rostrocaudal extent, but there was a clear demarcation of lateral and medial division. HRP-filled facial nucleus cells were ipsilateral to the injection site, and label appeared throughout the rostrocaudal length. All injection sites, including bulbar conjunctiva, labelled facial nucleus neurons located with overlapping distribution, predominantly in the dorsal part of the lateral division. Likewise, heavy labelling occurred throughout the entire ipsilateral cranial cervical ganglion and the trigeminal ganglion in all kittens. Injection of upper or lower eyelids caused some labelling in the second through the fourth cervical spinal ganglia.

Animals↗
PubMed1990

Absence of an osseous patella and other observations in Macropodidae stifle.

The patella is a large sesamoid bone that typically develops in the tendon of insertion of the large extensor muscles of the stifle joint. Although present in almost all species of mammals and birds, it has been found to be absent in the red kangaroo and two wallaby species (family Macropodidae). In its place is a fibrocartilage pad, located in the tendon of the quadriceps femoris muscle. This structure is visible grossly, is palpable, and has the form normally expected of a bony patella. In addition, the femoral trochlea is shallow and asymmetric, and the lateral gastrocnemius sesamoid is unusually prominent. These and other related modifications in the area of the Macropodidae stifle are presented.

Animals↗
PubMed1990

A simplified method of casting the macroscopic airways of lungs.

A technique for preparing casts of the macroscopic airways of mammalian lungs, which is both simplified and inexpensive in comparison with previous techniques, is described. The models are accurate, durable and flexible, and clearly demonstrate the orientation and branching pattern of the bronchial tree. The nature of the procedure also extends the availability of casts to laboratories or individuals with limited instrumentation and/or funding. Preliminary results using this technique to inject the lungs and certain air sacs of birds are also discussed.

Animals↗
PubMed1990

Horseradish peroxidase study of the location of extrinsic efferent and afferent neurons innervating the colon of dogs.

The abdominal portion of the colon of 13 clinically normal dogs was divided into 5 regions (ascending, transverse, left colic flexure, proximal descending, and distal descending), and each region was injected with 30 mg of horseradish peroxidase (HRP). The injected colonic region, brain stem, L7-Cd1 portion of the spinal cord, sympathetic trunk ganglia, celiacomesenteric ganglia, caudal mesenteric ganglion, pelvic plexi, distal vagal (nodose) ganglia, and L1-Cd1 spinal ganglia were obtained at post-injection hour 48, sectioned, and processed by use of the tetramethylbenzidine method. The entire length of the colon was found to be under extrinsic influence of the parasympathetic nucleus of cranial nerve X (PX), with the largest average number of labeled cells resulting from injection of the ascending colon. It was also indicated that the entire colon is under extrinsic influence of the sacral portion of the spinal cord because the pelvic ganglia (second-order neurons) of the pelvic plexi contained labeled cells for all colonic regions. The largest average number of labeled cells in pelvic ganglia was seen after injection of the distal portion of the descending colon. Only after injection of the distal portion of the descending colon were labeled cells found in the S1-S3 portion of the spinal cord. Labeled cells in the PX, spinal cord, and pelvic ganglia were found bilaterally. Although the entire abdominal portion of the colon appears to be influenced by cranial and sacral parasympathetic preganglionic (via pelvic ganglia) neurons, the relative importance of the 2 areas seems to be reversed between the ascending colon and distal portion of the descending colon.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1989

The location of extrinsic efferent and afferent nerve cell bodies of the normal canine stomach.

The location of the extrinsic efferent and afferent nerve cell bodies to the mucosa, submucosa, and tunica muscularis of the cardiac, gastric, and pyloric gland regions of the ventral stomach and to the mucosa-submucosa alone of these 3 glandular gastric regions was determined using the horseradish peroxidase technique. All animals of the study demonstrated labeling bilaterally in the rostrocaudal extent of the dorsal motor nucleus of the vagus nerve (DMV) although mucosa-submucosa injections resulted in fewer labeled cells in the DMV. There was no evidence of viscerotopic organization within the DMV for the different gastric regions. However, the left nucleus generally contained a greater number of labeled cells than the right nucleus. Injection of the mucosa, submucosa, and tunica muscularis of the cardiac gland region also resulted in labeling in the nucleus ambiguus in 4 of 5 animals. The vast majority of labeled postganglionic sympathetic neurons were found in the celiacomesenteric ganglion. Labeled cells were also located variously in the stellate ganglion, middle cervical ganglion, and sympathetic trunk ganglia for the different groups. There was no discernible pattern of localization of labeled cells within a sympathetic ganglion. For the stomach, afferent labeled cells were located in the range of the first thoracic to fourth lumbar spinal ganglia and the nodose ganglia, bilaterally. As with sympathetic neurons, there was no discernible pattern of localization of labeled cells within a sensory ganglion.

Animals↗
PubMed1986

The origins of innervation of the canine caudal pharyngeal muscles: an HRP study.

In deglutition, movements of the tongue and oropharynx direct a bolus to the laryngopharynx. The major muscles of this region, which includes the 'cricopharyngeal sphincter', must undergo sequential relaxation and contraction for correct swallowing action. The innervation of the caudal pharyngeal muscles involved in this action in the dog have not been determined previously by sensitive neuroanatomical techniques. In this study, the location of efferent and afferent neurons innervating the left cricopharyngeus, thyropharyngeus and hyopharyngeus muscles was determined by horseradish peroxidase (HRP) histochemistry in 7 puppies. Labeled cells were found ipsilaterally in the supraspinal nucleus, nucleus ambiguus (including nucleus retrofacialis) and nucleus intercalatus of all animals, in the parasympathetic nucleus of X (dorsal vagal efferent nucleus) of 6 animals, and in the hypoglossal nucleus of 4 animals. Small numbers of HRP-labeled cells were found contralaterally in the supraspinal nucleus of all animals, and in the rostral nucleus ambiguus, in the nucleus intercalatus and the parasympathetic nucleus of X of fewer animals. This defines a more extensive source of efferent neurons for these muscles than had been reported for the cat. Labeled postganglionic sympathetic neurons were found bilaterally in the cranial (superior) cervical, middle cervical and cervicothoracic (stellate) ganglia. Labeled afferent neurons were seen bilaterally in the proximal vagal (jugular) and distal vagal (nodose) ganglia and in the C1-C4 spinal ganglia. The location of sympathetic and sensory nerve cell bodies of the muscles of the laryngopharynx has not been previously reported.

Animals↗
PubMed1986

Percutaneous transtracheal ventilation and morphometric measurements of cervical structures in swine.

Fifteen swine cadavers were examined to determine a quick, reliable means of locating the level of the cricothyroid ligament from consistently palpable structures in the head and neck area. From calculations of measurements made on these cadavers, it was discovered that when a 21-43 kg pig was placed in a standard position, the measured length (L) from the angle of the mandible to the manubrium sterni multiplied by a factor of 0.48 equals the parameter Z [L (0.48) = Z]. Z was measured, beginning at the manubrium sterni, along the ventral midline. The endpoint of Z was at the level of the cricothyroid ligament. A catheter inserted at this point through the ligament into the airway provides a means of transtracheal ventilation. This method of ventilation can be used in emergencies to avoid a tracheostomy or as an alternative to endotracheal ventilation. This method was applied successfully to four anesthetized pigs as determined by a series of arterial blood gas samples.

Animals↗
PubMed1985

The origins of innervation of the esophagus of the dog.

This study defined the origins of extrinsic efferent and afferent innervation of the normal canine esophagus. When all the layers of the wall of the 3 esophageal regions (cervical, thoracic and abdominal) were injected with horseradish peroxidase (HRP), labeled nerve cells were found in the nucleus ambiguus (NA) and parasympathetic nucleus of X (PX) of the brainstem. Most labeled cells in the NA were located in the compact column (retrofacial nucleus) while labeled cells in the PX were located in separate rostral and caudal areas. There was no somatotopic organization in either the NA or PX. Labeled sympathetic postganglionic neurons were found in the cranial cervical, middle cervical, cervicothoracic, thoracic sympathetic trunk and celiacomesenteric ganglia. The HRP injection of the esophageal wall labeled sensory cell bodies in the glossopharyngeal, proximal and distal vagal, and C2-T6 spinal ganglia. There was no discernible pattern of distribution of labeled cells in the autonomic or sensory ganglia. When the HRP injections were confined to the mucosa-submucosa layers of the thoracic esophagus, a small number of labeled cells were identified in the NA; however, no labeled cells were found in the NA when injections were confined to the mucosa-submucosa of either the cervical or abdominal esophageal regions. With these confined injections, the labeled nerve cells appeared in the rostral part of the PX. Thus, it appeared that the internal tunics of the esophagus (i.e., the mucosa and submucosa) were innervated by neurons in the rostral PX while the muscular tunic was innervated by neurons in the caudal PX and the rostral NA. After mucosa-submucosa injections, labeled sympathetic neurons appeared in the same ganglia that were identified after whole wall injections and these had a similar random distribution. These injections also labeled neurons in the glossopharyngeal, proximal vagal, and distal vagal ganglia, but unlike the whole wall injections there was no labeling in the spinal ganglia. This suggested that the labeled cells of the spinal ganglia seen after whole wall injections conveyed impulses from the tunica muscularis and serosa.

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