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J S Eisenman

Publications and source records attributed to J S Eisenman.

12 recordsLinked to original sources
PubMed1986

Localization of responses in the somatosensory thalamus of the rat.

In the monkey and cat electrophysiological studies have indicated that unit response characteristics can be correlated with anatomical divisions in the somatosensory thalamus. In the rat, however, one study has suggested that the ventrobasal (VB) and posterior (PO) complexes are not functionally distinct [7]. In the present study, therefore, an attempt was made to correlate anatomical localization and unit response characteristics in the rat. We found that in the VB complex, units responding to light touch (LT) were more common than in the PO complex (45% vs. 9%), while in the PO complex, nociceptive units were more numerous than in the VB complex (55% vs. 38%). In the VB complex LT units had a somatotopic organization; in the PO complex they did not. Within the VB complex all LT units in the ventral posteromedial nucleus had receptive fields on the head; most ventral posterolateral nucleus LT units had receptive fields on the body. These results indicate that a correlation between unit response characteristics and localization does exist in the rat.

Afferent Pathways↗
PubMed1984

An immunocytochemical study of the serotonergic innervation of the thalamus of the rat.

The serotonergic innervation of the rat thalamus was studied with an indirect immunocytochemical technique using an antiserum raised against a serotonin-hemocyanin conjugate in animals pretreated with L-tryptophan and a monoamine oxidase (MAO) inhibitor. When pretreatment was not used there was a decrease in the number of immunoreactive fibers observed in the thalamic region. Innervation was greatest in nucleus ventralis corporis geniculati lateralis, and in the following midline nuclei: nucleus periventricularis, nucleus rhomboideus, and nucleus reuniens. Also well labeled were nucleus anterior ventralis, the intralaminar nuclei, and nucleus lateralis dorsalis. Moderate innervation was found in nucleus reticularis, nucleus anterior dorsalis, nucleus ventralis medialis, nucleus lateralis pars posterior, the posterior complex, and in nucleus dorsalis corporis geniculati lateralis. Very few serotonergic fibers were observed in nucleus paratenialis, nucleus gelatinosus, nucleus anterior medialis, nucleus medialis dorsalis, nucleus ventralis, nucleus ventralis pars dorsomedialis, or in nucleus corporis geniculati medialis. Serotonin immunoreactivity was also noted in a number of fiber bundles in the thalamic region. These include the fasciculus retroflexus, the fasciculus mamillothalamicus, the stria medullaris, and the stria terminalis. These results differ from those of previous descriptions of the serotonergic innervation of thalamic nuclei most notably in the midline nuclei and in the posterior complex. In this study the midline nuclei, nucleus rhomboideus, and nucleus reuniens were more densely innervated than had been described, and in the posterior complex a moderate, rather than sparse, innervation was observed. The more densely innervated nuclei of the anterior and lateral nuclear groups, nucleus lateralis dorsalis and nucleus anterior ventralis, also contained a greater number of labeled fibers than had been indicated.

Animals↗
PubMed1984

5-HT-Immunoreactive fibers in the trigeminal nuclear complex of the rat.

The distribution of serotonin immunoreactive (5-HT-IR) fibers in the trigeminal nuclear complex of the rat was mapped. In the sensory nuclei, innervation appeared to be dense in areas primarily related to nociceptive afferent activity, and sparse in areas primarily related to nonnociceptive afferent activity. Specifically, the marginal and gelatinosa layers of the spinal subnucleus caudalis contained many 5-HT-IR fibers while few labeled fibers were seen in the magnocellular portion of subnucleus caudalis or in the principal sensory nucleus. The spinal subnuclei oralis and interpolaris were sparsely innervated except for a few areas which contained more 5-HT-IR fibers. The motor nucleus contained as many immunoreactive fibers as the subnucleus caudalis, although fibers in the motor nucleus were thicker and varicosities more irregularly spaced than in caudalis.

Animals↗
PubMed1983

Response of rat superior salivatory units to chorda tympani stimulation.

Unit responses to chorda tympani stimulation in urethane anesthetized rats were characterized by response latency and frequency following ability. One hundred and fifty one units responded with constant latencies, mean: 16.9 msec, S.D.: 7.8 msec. Responses recorded from within the superior salivatory nucleus (SSN) had significantly longer latencies (18.8 +/- 6.8, n = 94) than those from surrounding areas (13.5 +/- 8.3, n = 50) (p less than 0.001). This difference was due to the higher incidence of responses with latencies between 2.7 and 10 msec outside of the SSN (44%) compared to SSN responses (8%). Ability to follow high frequency stimulation ranged from 2-550 Hz, and was the same for SSN neurons and those outside the nucleus. The population of responses localized to the SSN, with latencies greater than 10 msec and with high (greater than 100 Hz) frequency following, had a mean latency of 20.5 msec. The estimated conduction velocity for these presumed preganglionic, parasympathetic neurons is 0.85 M/sec +/- 0.25, significantly slower than that reported for similar responses in cats. The antidromic nature of these responses requires confirmation.

Animals↗
PubMed1982

Physiological stimulation enhances HRP marking of salivary neurons in rats.

Neurons of the superior salivary nucleus in rats have been labeled by retrograde transport of HRP injected into the lingual nerve. The nucleus is formed by a band of small, multipolar cells diagonally oriented in the lateral reticular formation of the caudal pons, just caudal to the root of the facial nerve. As time for transport of HRP was increased from 14 1/2 to 24 hr, the number of labeled cells increased exponentially along the curve, Y = 0.001 exp(0.51T), r = 0.995, to a maximum of 272 cells. Stimulating neuronal activity immediately after HRP injection, by swabbing the rat's mouth with 1% acetic acid, increased the number of labeled cells at 14 1/2 (p less than 0.05), 16, 18 and 20 (p less than 0.01) hr transport time. Counts of labeled cells in stimulated animals fell along a cumulative, normal distribution curve (ogive) with a mean at 18.2 hrs, S.D. 1.6 hr. Enhanced labeling of activated cells could be due to more rapid transport rates or to increased amounts of HRP transported.

Afferent Pathways↗
PubMed1970

Microelectrophoresis of biogenic amines on hypothalamic thermosensitive cells.

The rat hypothalamus contains thermally insensitive, normally sensisitive, and highly thermosensitive cells. The responses of thermosensitive neurons to microelectrophoretically applied acetylcholine, norepinephrine, and 5-hydroxy-tryptamine were the same in both rats and cats. The firing rate of warm-sensitive interneurons was accelerated by acetylcholine and inhibited by norepinephrine. The firing rate of cool-sensitive interneurons was accelerated by norepinephrine and, in one case, was inhibited by 5-hydroxytryptamine. Thermodetector cells were relatively insensitive to these amines, but were sensitive to current flow. These results from the rat, but not from the cat, agree with the data for thermoregulatory responses following microinjection of these amines into the hypothalamus.

Acetylcholine↗