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Application of optical recording to rat area postrema in response to vagal nerve stimulation
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11. Central autonomic control I n t e r l e u k i n I - B ON EFFERENT ACTIVITY OF THE SPLENIC AND ADRENALBRANCH OF THE SPLANCHlqIC NERVE. AKIRA NIIJI~IA" , TETSURO HORI" " , SHUJI AOU" " " AND YUTAKA OOHURA" " " , Department of Physiology" ~ Nii6ata U n i v e r s i t y School of Medicine, Niigata; Department of Physiology " , Saga Medical College, Saga; National I n s t i t u t e of Physiology" " " , Okazaki; Japan. Reportedly, the autonomic nervous system plays some role in modulation of immune system function. Under anesthesia with urehtane, e f f e c t of i . v . administration of I n t e r l e u k i n 1-B was observed in rat. An increase in e f f e r e n t discharge was observed in s p l e n i c and adrenal nerves. The l e a s t e f f e c t i v e dose was 20pg per animal. Responses were dose dependent. Response u s u a l l y l a s t e d for a few hours. Increased discharge rate was c a n c e l l e d by i . v . administration of ihuprofen (6mg) and suppressed by s a l i c y l i c acid (20mg). The r e s u l t s suggest that I n t e r l e u k i n modulates the function of immune system due to a c c e l e r a t i o n of e f f e r e n t a c t i v i t y of s p l e n i c and adrenal nerves. EFFECT OF AMBIENT TEMPERATURE .O1~1 DISCHARGE PATTERNS OF SKIN SYMPATHEF+~)(~ NERVE A C T I V I T Y IN MAN. SATOSHI IWASE , T A D A A K I MANO 1), AND JUNICHI SUGENOYA ~/, 1) The Research Institute of Environmental Medicine I Nagoya Universityl Nagoya 464-011 and 2) Second Department of Physiology I Aichi Medical University, Aichi 480-111 Japan. Skin sympathetic nerve a c t i v i t y (SSA) is composed of sudomotor (SM) and vasoconstrictor (VC) components. To c l a r i f y the e f f e c t of ambient temperature on SM and VC components of SSA, postganglionic sympathetic e f f e r e n t nerve discharges leading to the palmar, plantar, and dorsum pedis skin were observed microneurographically under d i f f e r e n t temperature conditions. To identify SM and VC components, SSA was recorded simultaneously with sweat rate and skin blood flow. Sweat rate was recorded by a ventilated capsule device (hidrograph), and skin blood flow was recorded by laser Doppler flowmeter and photoelectric plethysmograph. Sensory stimulation (electric stimulation of the nerve trunk, application of sound, or pinprick) elicited reflex biphasic SSA bursts with latencies of approximately 0.6 and 1.2 sec, followed by a rise in sweat rate with almost constant latency of about 2.4 sec, and a reduction in skin blood flow with a latency of about 6.3 sec. Reflex and spontaneous SSA bursts were d i f f e r e n t i a t e d into SM or VC, followed by rise in sweat rate or reduction in skin blood flow, respectively, with the above mentioned latencies. SM bursts were of shorter duration than VC ones. The spontaneous SSA was prominently enhanced by increase of temperature to 34°C, due to increased SM component. Below 15°C, all SSA bursts changed into VC. SSA has its lowest act i vi t y at around 22°C to 24°C, and became enhanced when temperature was either elevated or lowered. We conclude that SSA component transfers from VC dominant to SM dominant with elevation of ambient temperature, and vice versa with lowering temperature. APPLICATION OF OPTICAL RECORDING TO RAT AREA POSTREMA IN RESPONSE TO VAGAL N E R V E STIMULATION. SHIN-ICHI ITO, Dept. Physiol., Kumamoto Univ. Med. Sch., Honjo 2-2-1, Kumamoto, 860, Japan. Rat area postrema (nAP) and adjacent solitary tract nucleus are visually accesible by cerebellectomy and drivable by vagal nerve stimulation, with this preparation, optical recording with voltage sensitive dyes was applied to intact mammalian central nervous system. Rats were anesthetized with sodium amobarbital, connected with stimulating electrodes to bilateral cervical vagal trunk, mounted on a stereotaxic apparatus and c e r e b e l l e c t o m i z e d with aspiration to expose the dorsal surface of the brainstem, which was then stained for an hour with the styryl dye RH414 at 0.5-4.0 mg/ml in physiological solution. Histologically, the dye was proven to penetrate beyond AP. After rinsing excess dye, optical signals were examined with a photodiode through a fluorescence microscope with epi-illumination. A large change in fluorescence intensity of low frequency, synchronous to ECG, was eliminated through a low cut filter. After averaging, a small fractional change (10 -5 ) time-locked to the stimulus was detected, with similar onset latency to that of the field potentials. This deflection was modified in form, or even eliminated, by changing the incident light wavelength. After prolonged recording session, in spite of unchanged b a c k g r o u n d intensity, this signal lowered in size, which became demonstrable when retained with the dye. Thus, with using voltage sensitive dye, the activity of rat brainstem can be optically m o n i t o r e d in situ.
11. Central autonomic control I n t e r l e u k i n I - B ON EFFERENT ACTIVITY OF THE SPLENIC AND ADRENALBRANCH OF THE SPLANCHlqIC NERVE. AKIRA NIIJI~IA" , TETSURO HORI" " , SHUJI AOU" " " AND YUTAKA OOHURA" " " , Department of Physiology" ~ Nii6ata U n i v e r s i t y School of Medicine, Niigata; Department of Physiology " , Saga Medical College, Saga; National I n s t i t u t e of Physiology" " " , Okazaki; Japan. Reportedly, the autonomic nervous system plays some role in modulation of immune system function. Under anesthesia with urehtane, e f f e c t of i . v . administration of I n t e r l e u k i n 1-B was observed in rat. An increase in e f f e r e n t discharge was observed in s p l e n i c and adrenal nerves. The l e a s t e f f e c t i v e dose was 20pg per animal. Responses were dose dependent. Response u s u a l l y l a s t e d for a few hours. Increased discharge rate was c a n c e l l e d by i . v . administration of ihuprofen (6mg) and suppressed by s a l i c y l i c acid (20mg). The r e s u l t s suggest that I n t e r l e u k i n modulates the function of immune system due to a c c e l e r a t i o n of e f f e r e n t a c t i v i t y of s p l e n i c and adrenal nerves. EFFECT OF AMBIENT TEMPERATURE .O1~1 DISCHARGE PATTERNS OF SKIN SYMPATHEF+~)(~ NERVE A C T I V I T Y IN MAN. SATOSHI IWASE , T A D A A K I MANO 1), AND JUNICHI SUGENOYA ~/, 1) The Research Institute of Environmental Medicine I Nagoya Universityl Nagoya 464-011 and 2) Second Department of Physiology I Aichi Medical University, Aichi 480-111 Japan. Skin sympathetic nerve a c t i v i t y (SSA) is composed of sudomotor (SM) and vasoconstrictor (VC) components. To c l a r i f y the e f f e c t of ambient temperature on SM and VC components of SSA, postganglionic sympathetic e f f e r e n t nerve discharges leading to the palmar, plantar, and dorsum pedis skin were observed microneurographically under d i f f e r e n t temperature conditions. To identify SM and VC components, SSA was recorded simultaneously with sweat rate and skin blood flow. Sweat rate was recorded by a ventilated capsule device (hidrograph), and skin blood flow was recorded by laser Doppler flowmeter and photoelectric plethysmograph. Sensory stimulation (electric stimulation of the nerve trunk, application of sound, or pinprick) elicited reflex biphasic SSA bursts with latencies of approximately 0.6 and 1.2 sec, followed by a rise in sweat rate with almost constant latency of about 2.4 sec, and a reduction in skin blood flow with a latency of about 6.3 sec. Reflex and spontaneous SSA bursts were d i f f e r e n t i a t e d into SM or VC, followed by rise in sweat rate or reduction in skin blood flow, respectively, with the above mentioned latencies. SM bursts were of shorter duration than VC ones. The spontaneous SSA was prominently enhanced by increase of temperature to 34°C, due to increased SM component. Below 15°C, all SSA bursts changed into VC. SSA has its lowest act i vi t y at around 22°C to 24°C, and became enhanced when temperature was either elevated or lowered. We conclude that SSA component transfers from VC dominant to SM dominant with elevation of ambient temperature, and vice versa with lowering temperature. APPLICATION OF OPTICAL RECORDING TO RAT AREA POSTREMA IN RESPONSE TO VAGAL N E R V E STIMULATION. SHIN-ICHI ITO, Dept. Physiol., Kumamoto Univ. Med. Sch., Honjo 2-2-1, Kumamoto, 860, Japan. Rat area postrema (nAP) and adjacent solitary tract nucleus are visually accesible by cerebellectomy and drivable by vagal nerve stimulation, with this preparation, optical recording with voltage sensitive dyes was applied to intact mammalian central nervous system. Rats were anesthetized with sodium amobarbital, connected with stimulating electrodes to bilateral cervical vagal trunk, mounted on a stereotaxic apparatus and c e r e b e l l e c t o m i z e d with aspiration to expose the dorsal surface of the brainstem, which was then stained for an hour with the styryl dye RH414 at 0.5-4.0 mg/ml in physiological solution. Histologically, the dye was proven to penetrate beyond AP. After rinsing excess dye, optical signals were examined with a photodiode through a fluorescence microscope with epi-illumination. A large change in fluorescence intensity of low frequency, synchronous to ECG, was eliminated through a low cut filter. After averaging, a small fractional change (10 -5 ) time-locked to the stimulus was detected, with similar onset latency to that of the field potentials. This deflection was modified in form, or even eliminated, by changing the incident light wavelength. After prolonged recording session, in spite of unchanged b a c k g r o u n d intensity, this signal lowered in size, which became demonstrable when retained with the dye. Thus, with using voltage sensitive dye, the activity of rat brainstem can be optically m o n i t o r e d in situ.