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Y Torigata

Publications and source records attributed to Y Torigata.

7 recordsLinked to original sources
PubMed1978

Excitatory and inhibitory electrodermal reflexes evoked by cutaneous stimulation in acute spinal cats.

The electrodermal reflex (EDR) was recorded from the paws of acute spinal cats by a DC potential recording method. The EDR was produced either by pinching the skin in various areas of the trunk, or by electrical stimulation of cutaneous afferents of various spinal segments. It was found that not only excitatory but also inhibitory EDRs were produced and that occurrence of the excitatory and inhibitory EDRs depended on both the segmental position and the laterality of the stimulated area. Cutaneous stimulation generally produced excitatory EDRs more frequently than inhibitory ones, except when afferent inputs entered the spinal cord at or close to the segments of sudomotor outflow; in the latter case inhibitory EDRs were comparatively frequent and strong. Maximal inhibitory EDRs were elicited by stimulation of the group II afferent fibers of the cutaneous nerves only, whereas maximal excitatory EDRs were elicited after stimulation of the group II, III and IV afferent fibers of cutaneous origin.

Animals↗
PubMed1976

Varying changes in heart rate produced by nociceptive stimulation of the skin in rats at different temperatures.

The effect of nociceptive stimulation of various skin areas of the neck, chest and abdomen on the heart rate was examined in anesthetized rats with the cord intact and in acute spinal rats, at different body temperatures. In the anesthetized rats with the cord intact, the stimulation on the neck, chest and abdominal skin areas caused reflex changes in heart rate. At a rectal temperature of 38.0-38.9 degrees C the response was usually an increase in heart rate, whereas the response at 36.0-36.9 degrees C was a decrease. The heart rate reflex response at 37.0-37.9 degrees C was a monophasic increase or decrease, or a biphasic initial decrease followed by an increase. The reflex increase or decrease in heart rate produced by cutaneous stimulation was mediated by a reflex increase or decrease in the efferent discharges of the cardiac sympathetic nerve. In acute spinal rats, only stimulation on the chest skin area, at a rectal temperature of 36.0-38.9 degrees C, would always produce a reflex increase in heart rate. This reflex increase in heart rate was also produced by an increase in efferent discharges of the cardiac sympathetic nerve.

Abdomen↗
PubMed1975

Changes in vesical function produced by cutaneous stimulation in rats.

(1) The effect of stimulation of various skin areas on the function of the bladder was examined in anesthetized rats with the CNS intact, in decerebrated non-anesthetized rats and in spinal rats. The tone and contraction of the bladder was measured by the intravesical ballon method. (2) When the volume of the intravesical ballon was expanded so that the resting vesical pressure was increased from O to approximately 40 mm H2O level, the bladder revealed small spontaneous contractions in all experiments. Under these conditions intravesical pressure was increased approximately 40 mm H2O by application of tactile or nociceptive stimulation of the skin in the perineal area. This excitatory perneal-bladder response existed befor and after spinal transection and was shown to be a propriospinal reflex for which reflexly increased nerve discharges of vesical branches of the pelvic nerves were responsible. (3) When the volume of the intravesical ballon was further expanded so that the resting vesical pressure was kept about 200 mm H2O, the bladder had the usual large rhythmic contractions (micturition contractions) with amplitudes of about 610 mm H2O, and rhythms of 1--3/min in the CNS intact or decrebrated rats. These large contractions were driven by the rhythmic bust discharges of the vesical nerve branches of the pelvic nerves. The occurrence of the large contractions of the bladder could be inhibited by nociceptive stimulation which was localized in the perineal area. This inhibition of the large contractions was caused by disappearance of the rhythmic burst discharges in the vesical branches of the pelvic nerves. (4) On some occasions in the CNS intact anesthetized and in the decerebrated non-anesthetized rats the large contractions of the bladder disappeared during experiments even when the bladder was expanded enough for producing normal large contractions and kept at high intravesical pressure. Regardless of whether the large contractions existed or not at the high intravesical pressure, the vesical pressure was increased by perineal stimulation due to the same neural mechanism mentioned in (2) above.

Animals↗
PubMedDate not supplied

Somato-vesical reflexes in chronic spinal cats.

The effects of afferent volleys in hindlimb cutaneous and muscle nerves on vesical tone and contractility and on the discharges in pelvic nerves to the bladder were measured in anesthetized CNS-intact and 2-19 months chronic spinal cats. In chronic spinal cats volleys in group III and IV fibers increased the tone of the quiet, empty bladder (excitatory somato-vesical reflex). The same volleys inhibited the slow, large, rhythmic micturition contractions of the expanded bladder (inhibitory somato-vesical reflex). In CNS intact cats single or short tetanic volleys induced a reflex discharge in pelvic vesical nerve branches with 3 distinct components. These reflexes could be observed during micturition contractions, not markedly between the contractions or when the bladder was empty and quiet. The latencies of the 3 components were 90, 320 and 770 ms, respectively. The two early components (AI- and A2-reflex) were evoked by volleys in group II and III hindlimb afferents. The late component (C-reflex) was induced by group IV volleys. In chronic spinal cats a group II and III-induced A-reflex (latency 90 ms) and a group IV-induced C-reflex (latency 340 ms) were observed. The central pathways and the physiological significance of the various somato-vesical reflexes are discussed.

Afferent Pathways↗