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Biomedical subjects

R L Kitchell

Publications and source records attributed to R L Kitchell.

At least 37 records · Page 2Linked to original sources
PubMed1984

Cutaneous innervation of the thorax and abdomen of the dog.

The anatomy of the cutaneous nerves innervating the canine thorax and abdomen was investigated by gross dissection of 38 dogs. Additionally, the cutaneous areas innervated by the thoracic and abdominal cutaneous nerves were mapped in a 2nd group of 33 barbiturate-anesthetized male dogs, using electrophysiologic techniques. The skin of the thorax was innervated by dorsal cutaneous branches, lateral cutaneous branches, and ventral cutaneous branches of the spinal nerves. The dorsal cutaneous branches were branches of the dorsal primary branches of spinal nerves C6 and T2 through T11. The lateral cutaneous branches were branches of the ventral primary branches of spinal nerves T2 through T12. The ventral cutaneous branches were branches of the ventral primary branches of spinal nerves T2 through T10. The skin of the abdomen was innervated by dorsal and lateral cutaneous branches of spinal nerves T12 through L3 (and occasionally L4). The cutaneous areas of the dorsal cutaneous branches occupied the dorsal half of the scapular and thoracic regions and the dorsal 2/5 of the abdominal region. The cutaneous areas of the lateral cutaneous branches covered the major portion of the ventral half of the thorax and the ventral 3/5 of the abdomen. The cutaneous areas of the ventral cutaneous branches occupied the axilla and the ventral part of the thoracic wall.

Abdomen↗
PubMed1983

Sensory nerve conduction velocities in forelimb of ponies.

Normal nerve conduction velocity values in 10 ponies were determined for sensory nerve fibers in the median and ulnar nerves. A percutaneous signal-averaging technique was developed and used. Medial and lateral palmar digital nerves on the abaxial surface of the proximal sesamoid bones were used as the sites for percutaneous stimulation, whereas recording sites included the medial and lateral palmar nerves just distal to the carpus and the median and ulnar nerves in the middle of the radius. Sensory nerve conduction velocities can be evaluated simply and clinically in the limbs of horses, using percutaneous signal-averaging techniques.

Action Potentials↗
PubMed1983

Electrophysiologic studies of the cutaneous nerves of the head of the dog.

The cutaneous nerves of the head of the dog were investigated in 16 barbiturate-anesthetized dogs. The electrophysiologic demonstration of afferent impulses in a given cutaneous nerve to the movement of hairs within an area of skin was used to delineate the nerve's cutaneous area (CA) of innervation. In this manner, the CA for the cutaneous branches of the trigeminal nerve, the facial nerve, and the 2nd, 3rd, and 4th cervical nerves were determined. The CA of adjacent cutaneous nerves were found to overlap extensively. The portion of a nerve's CA which was solely innervated by it was termed the autonomous zone. Most of the CA of the head was innervated by branches of the trigeminal nerve. The internal auricular branches of the facial nerve innervated the majority of the concave surface of the pinna. The branches of the 2nd cervical nerve supplied a large CA which extended from the caudal intermandibular space to the dorsal midline and apex of the pinna. The CA of the branches of the 3rd and 4th cervical nerves occupied much of the cervical area cranial to the scapula and caudal to the hyoid apparatus. A CA was not found for the 1st cervical nerve.

Animals↗
PubMed1983

Electrophysiologic and behavioral studies of the cutaneous nerves of the concave surface of the pinna and the external ear canal of the dog.

The investigation used 2 methods to study the cutaneous innervation of the concave surface of the pinna of the dog: electrophysiologic and behavioral. The cutaneous innervation of the external ear canal was studied, using electrophysiologic methods. On one side of each dog, the area of remaining sensitivity for the 3 internal auricular branches of the facial nerve (InAuB-FN) was determined by sectioning the rostral auricular nerve, dorsal cutaneous branch of the second cervical nerve, and great auricular nerve and then examining the dogs 1 week later. The cutaneous area (CA) of each branch of the InAuB-FN was then determined electrophysiologically. These individual CA were combined to obtain a composite cutaneous area (Comp-CA) for the InAuB-FN. By comparing the Comp-CA with the area of remaining sensitivity, it was determined that they defined essentially the same regions. On the opposite side of each dog, the InAuB-FN were surgically transected and the resultant areas of anesthesia were determined approximately 1 week after the sectioning was done. The cutaneous region thus delineated represented a zone solely innervated by these branches of the FN. Next, the CA for the rostral auricular nerve, dorsal cutaneous branch of the second cervical nerve, and great auricular nerve to the pinna's concave surface were determined electrophysiologically in each dog. The cutaneous zone enclosed by the margins of the CA of these 3 nerves represented the composite autonomous zone for the InAuB-FN. The behaviorally determined area of anesthesia was essentially the same area as the composite autonomous zone. The skin lining the vertical portion of the external ear canal was supplied by all 3 branches of the InAuB-FN. The skin lining the horizontal portion of the external ear canal was supplied by the lateral branch of the InAuB-FN and the external acoustic meatus branch of the auriculotemporal nerve.

Animals↗
PubMed1982

Electrophysiologic studies of cutaneous nerves of the forelimb of the cat.

The cutaneous innervation of the forelimb was investigated in 20 barbiturate-anesthetized cats by using electrophysiological techniques. The cutaneous area (CA) innervated by each cutaneous nerve was delineated in at least six cats by brushing the hair in the CA with a small watercolor brush while recording from the nerve. Mapping of adjacent CA revealed larger overlap zones (OZ) than were noted in the dog. Remarkable findings were that the brachiocephalic nerve arose from the axillary nerve and the CA comparable to that supplied by the cutaneous branch of the brachiocephalic nerve in the dog was supplied by a cutaneous branch of the suprascapular nerve. The CA supplied by the communicating branch from the musculocutaneous to the median nerve was similar in both species except that the communicating branch arose proximal to any other branches of the musculocutaneous nerve in the cat, whereas it was a terminal branch in the dog. The superficial branch of the radial nerve gave off cutaneous brachial branches in the cat proximal to the lateral cutaneous antebrachial nerve. The CA of the palmar branches of the ulnar nerve did not completely overlap the CA of the palmar branches of the median nerve as occurred in the dog; thus an autonomous zone (AZ) for the CA of the palmar branches of the median nerve is present in the cat, whereas no AZ existed for the CA of this nerve in the dog.

Animals↗
PubMed1982

Spinal nerve root origins of the cutaneous nerves arising from the canine brachial plexus.

The spinal nerve root origins of the cutaneous nerves arising from the brachial plexus were investigated in 10 babiturate-anesthetized dogs by stimulating dorsal roots C5 to T2 and recording from each cutaneous nerve. Upon completion of the experiment, the contributions of the spinal nerve ventral branches to the brachial plexus were verified by anatomic dissection. The brachial plexus was formed by the ventral branches of C6 to T2 in 8 dogs, C6 to T1 in 1 dog, and C5 to T1 in 1 dog. The cutaneous branch of brachiocephalicus nerve was formed primarily by contributions from the C6 dorsal root. The cranial lateral cutaneous brachial nerve, a branch of the axillary nerve, was formed predominantly from C6 to C7. The median nerve received contributions primarily from C7, C8, and T1, and the communicating branch from the musculocutaneous to the median nerve contained fibers primarily from C7 and C8. The medial and lateral branches of the superficial branch of the radial nerve arose from C6, C7, C8, and T1, with the medial branch generally arising 1 segment craniad to the lateral. The palmar and dorsal branches of the ulnar nerve arose predominately from C8 and T1, and the caudal cutaneous antebrachial nerve of the ulnar arose predominately from T1 and T2.

Action Potentials↗
PubMed1982

Electrophysiologic studies of the thoracic limb of the horse.

The cutaneous innervation of the thoracic limb was investigated in 18 barbiturate-anesthetized horses, using electrophysiologic techniques. The cutaneous area (CA) innervated by each cutaneous nerve was delineated in at least 4 horses by stroking the hairs with a small watercolor brush while recording from the nerve. Mapping of adjacent CA revealed areas of considerable overlap. The part of a CA of a given nerve supplied only by that nerve is referred to as its autonomous zone (AZ). In contrast to the standard textbook illustrations cutaneous branches of the axillary, radial, musculocutaneous, and ulnar nerves overlapped extensively in the antebrachium. Clinically testable AZ were found in the antebrachium for the caudal cutaneous antebrachial nerve of the ulnar nerve and in the carpus and manus for the cutaneous branches of the median, ulnar, and musculocutaneous nerves; AZ were not found for the cutaneous branches of the radial and axillary nerves.

Animals↗
PubMed1980

Response of muscle spindle primary endings to static stretch in acute and chronic spinal cats.

To evaluate fusimotor activity, the response of muscle spindle primary endings to static stretch was recorded from group Ia fibers in 8 control cats and in 31 cats at 3, 6, 14, 30, and 60 days after lumbar spinal cord transection. The spindle responses and clinical status of each group were compared with those of the control group. At 3 days after transection, the cats were hypotonic and mildly hyperreflexic. Spindle responses were significantly depressed. By day 6, the cats were mildly hypertonic and significant spindle recovery had occurred, although the responses were still significantly depressed from control levels. Spindle responses, hypertonia, and hyperreflexia continued to increase to day 30. At this time, spindle responses remained significantly depressed, although the cats were markedly hypertonic and hyperreflexic. A significant change in spindle activity or clinical status did not occur from 30 to 60 days after transection.

Action Potentials↗
PubMed1980

Electrophysiologic studies of cutaneous nerves of the thoracic limb of the dog.

The cutaneous innervation of the thoracic limb was investigated in 36 barbiturate-anesthetized dogs, using electrophysiologic techniques. The cutaneous area (CA) innervated by each cutaneous nerve was delineated in at least five dogs by stroking the hair in the area with a small watercolor brush while recording from the nerve. Mapping of adjacent CA revealed areas of considerable overlapping. The part of the CA of a given nerve supplied by only that nerve is referred to as its autonomous zone. Of all nerves arising from the brachial plexus, only the suprascapular, subscapular, lateral thoracic, thoracodorsal, and cranial and caudal pectoral nerves lacked cutaneous afferents. The dorsal cutaneous branch of C6 had a CA, but no grossly demonstrable dorsal cutaneous branches for C7 C8, or T1 were found. The cervical nerves had ventral cutaneous branches, but no lateral cutaneous branches. Thoracic nerves T2-T4 had dorsal, ventral, and lateral cutaneous branches. The cutaneous branches of the brachiocephalic, axillary, musculocutaneous, radial, median, and ulnar nerves all had CA which were overlapped by adjacent CA, thus their autonomous zones were much smaller than the cutaneous areas usually depicted for these nerves in anatomy and neurology textbooks.

Animals↗
PubMed1978

Palatability studies of snail and slug poison baits, using dogs.

In 1975, the California Department of Food and Agriculture required registered manufacturers of snail and slug baits to present data showing the unattractiveness of these products to dogs, in order to reduce the number deaths in dogs due to poisoning by eating these baits. A cooperative project involving the University of California, the California Department of Food and Agriculture, and the snail and slug bait manufacturers was designed to assist the manufacturers in assessing the palatability of their products by dogs and to develop criteria for the regulatory agencies to use to ensure that the products they were registering were unattractive to dogs. The studies showed that most recently formulated baits were relatively unpalatable for dogs. A 2-panel consumption testing procedure was developed and is being used by the California Department of Food and Agriculture and the Environmental Protection Agency as criteria for registration. Current reports indicate a dramatic decrease in snail and slug bait poisonings in California after these criteria were established as requirements for registration of snail and slug baits.

Acetaldehyde↗
PubMed1978

Electrophysiology of the afferent innervation of the penis of the domestic ram.

1. The discharge of impulses in afferent fibres dissected from the dorsal nerve of the penis of chloralose-anaesthetized rams was recorded electrophysiologically during controlled natural stimulation of the surgically exposed penis maintained at body temperature and mechanically stabilized in a plaster of Paris mould. 2. Fifty-eight slowly adapting mechanorecptor units were examined and their pressure, velocity and displacement thresholds were determined. Units often responded best to integumental stretch. Few had resting discharges. During a sustained perpendicularly applied displacement most units adapted to silence within 1.5 min. The units were classified into types from an analysis of their adapted impulse trains in response to a sustained mechanical stimulus. 3. Twenty-five mechanoreceptive units had rapidly adapting responses. Most units had typical rapid adapting characteristics and discharged impulses only during the dynamic phase of the application of the displacement. A subgroup had intermediate adapting characteristics, and discharged intermittently during steady displacement of the integument. 4. The mechanical sensitivity of most receptors altered when the temperature of the receptive field was changed with a positive correlation in eleven units, a negative correlation in six. Six slowly adapting units were thermally insensitive. Twelve rapidly adapting units were tested. Six had a positive thermal correlation and four a negative correlation. 5. The conduction velocities of axons of mechanoreceptor units in the dorsal nerve of the penis were in the Aalpha range (12--77 msec-1). 6. Two specific warm and five specific cold units were found. The conduction velocities of the axons supplying warm receptors were 45.4 msec-1 (one unit) and those for cold receptors were 7.5, 7.8, 30, 45.5, 48.7 msec-1. 7. No correlation could be found between the receptor submodality and the profuse receptor end bulb population demonstrated histologically.

Action Potentials↗
PubMed1978

Physiologic properties of contraction of the canine cremaster and cranial preputial muscles.

Contraction properties of the cremaster and the cranial preputial muscles of 11 mature intact male dogs were investigated. Isometric recordings of muscle contractile tension were performed in situ. Muscle contractions were elicited by stimulating the severed motor nerves. Contraction times of 73.8 ms and 103.2 ms were obtained for the cremaster and the cranial preputial muslces, respectively. Application of repetitive stiumuli produced summation of contractions at low stimulus frequencies. Apparent tetanic fusion and maximum tetanic tension were also observed at relatively low stimulus frequencies, 30 Hz for the cremaster muscle and 28 Hz for the cranial preputial muscle. Optimum length for the cremaster muscle was coincident with its observed in situ resting length (+/- 5 mm), but the optimum length for the cranial preputial muslce deviated by some 20 to 25 mm above the resting length. Possible artifactual errors regarding the cranial preputial muslce's length-tension relationship are discussed.

Animals↗
PubMed1977

Comparative study of the dorsal motor nucleus of the vagus nerve.

Quantitative studies were made of cells in the dorsal motor nucleus of the vagus nerve in the horse, dog, cat, pig, sheep, goat, and calf. This nucleus was larger in ruminants than in nonruminants. Some cells in all parts of the nucleus supplied visceral structures in the head, cervical, thoracic, and abdominal regions; however, a definite topographic localization did exist within the nucleus. Eighty percent of the cells which supplied the abdominal viscera were in the rostral and rostral-middle regions. The cells which supplied the thoracic viscera were distributed almost equally within the rostral three-quarters of the nucleus. Seventy-three percent of the cells which supplied viscera in the head and neck regions were in the caudal-half of the nucleus. The rostral region of the nucleus was much larger in ruminants than in nonruminants. It is proposed that cells in the rostral region of the nucleus supply the highly developed rumen and reticulum.

Animals↗