• Title/Summary/Keyword: Cerebral Physiology

Search Result 264, Processing Time 0.022 seconds

Motor Areas of the Cerebral Cortex-New Vistas

  • Tanji, Jun
    • The Korean Journal of Physiology
    • /
    • v.28 no.1
    • /
    • pp.19-25
    • /
    • 1994
  • On the basis of morphological and functional studies, it is now established that there exist multiple motor representation areas in the frontal lobe of subhuman primates. Recent development of analysis on cerebral critical organization in human subjects, utilizing novel techniques of PET and MRI, provides evidence of corresponding motor areas. Each area has its unique sources of inputs from the thalamus and from other parts of the cerebral cortex. To understand functional roles of these multiple motor areas, it is necessary to study neural activity while subjects are performing a variety of motor tasks. In view of high accuracy in spatial and temporal resolution, the analysis of single cells in relation to specific aspects of motor behavior remains to be a powerful research technique. It is with this technique that a number of novel concepts on functional roles of multiple motor areas have been proposed.

  • PDF

Different Mechanisms for $K^+-Induced$ Relaxation in Various Arteries

  • Suh, Suk-Hyo;Park, Sung-Jin;Choi, Jai-Young;Sim, Jae-Hoon;Kim, Young-Chul;Kim, Ki-Whan
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.3 no.4
    • /
    • pp.415-425
    • /
    • 1999
  • $[K^+]_o$ can be increased under a variety of conditions including subarachnoid hemorrhage. The increase of $[K^+]_o$ in the range of $5{\sim}15$ mM may affect tensions of blood vessels and cause relaxation of agonist-induced precontracted vascular smooth muscle $(K^+-induced$ relaxation). In this study, effect of the increase in extracellular $K^+$ concentration on the agonist-induced contractions of various arteries including resistant arteries of rabbit was examined, using home-made Mulvany-type myograph. Extracellular $K^+$ was increased in three different ways; from initial 1 to 3 mM, from initial 3 to 6 mM, or from initial 6 to 12 mM. In superior mesenteric arteries, the relaxation induced by extracellular $K^+$ elevation from initial 6 to 12 mM was the most prominent among the relaxations induced by the elevations in three different ways. In cerebral arteries, the most prominent relaxation was produced by the elevation of extracellular $K^+$ from initial 1 to 3 mM and a slight relaxation was provoked by the elevation from initial 6 to 12 mM. In superior mesenteric arteries, $K^+-induced$ relaxation by the elevation from initial 6 to 12 mM was blocked by $Ba^{2+}\;(30\;{\mu}M)$ and the relaxation by the elevation from 1 to 3 mM or from 3 to 6 mM was not blocked by $Ba^{2+}.$ In cerebral arteries, however, $K^+-induced$ relaxation by the elevation from initial 3 to 6 mM was blocked by $Ba^{2+},$ whereas the relaxation by the elevation from 1 to 3 mM was not blocked by $Ba^{2+}.$ Ouabain inhibited all of the relaxations induced by the extracellular $K^+$ elevations in three different ways. In cerebral arteries, when extracellular $K^+$ was increased to 14 mM with 2 or 3 mM increments, almost complete relaxation was induced at 1 or 3 mM of initial $K^+$ concentration and slight relaxation occurred at 6 mM. TEA did not inhibit $Ba^{2+}-sensitive$ relaxation at all and NMMA or endothelial removal did not inhibit $K^+-induced$ relaxation. Most conduit arteries such as aorta, carotid artery, and renal artery were not relaxed by the elevation of extracellular $K^+.$ Among conduit arteries, trunk of superior mesenteric artery and basilar artery were relaxed by the elevations of $[K^+]_o.$ These data suggest that $K^+-induced$ relaxation has two independent components, $Ba^{2+}-sensitive$ and $Ba^{2+}-insensitive$ one and there are different mechanisms for $K^+-induced$ relaxation in various arteries.

  • PDF

The Mechanism Study of Prescription for Treatment Abundant Expectoration due to Deficiency of Qi on Brain Disease in Rats (기허담성치방이 뇌병환에 미치는 기전연구)

  • Lee Nam Goo;Seong Sin
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.18 no.4
    • /
    • pp.1083-1088
    • /
    • 2004
  • This Study was designed to investigate the mechanism of Prescription for Treatment Abundant Expectoration due to Deficiency of Qi(Yukgunja-Tang, YGT) on cerebral hemodynamics [regional cerebral blood f1ow(rCBF) and pial arterial diameter(PAD)] in cerebral ischemia rats. The results were as follows: Both rCBF and PAD were significantly and stably decreased by YGT (10㎎/㎏, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in Control group. Pretreatment with indomethacin(1㎎/㎏, i.p.), an inhibitor of cyclooxygenase and methylene blue(10㎍/㎏, i.p.), an inhibitor of guanylate cyclase significantly but unstably increased the YGT-induced increases in rCBF during the period of cerebral reperfusion. Pretreatment with indomethacin significantly and stably decreased the YGT-induced increases in PAD during the period of cerebral reperfusion, but pretreatment with methylene blue increased unstably the YGT-induced increases in PAD during the period of cerebral reperfusion. In conclusion, the present authors thought that mechanism of YGT on cerebral hemodynamics was connected with guanylate cyclase in cerebral ischemia rats.

Effects of Palmul-Tang on the Change of Cerebral Hemodynamics in Rats (팔물탕이 뇌혈류역학 변화에 미치는 효과)

  • Park Cheol Hun;Bae In Tae;Jeong Hyun Woo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.18 no.4
    • /
    • pp.1014-1020
    • /
    • 2004
  • The study was designed to investigate the effects of Palmul-Tang(PMT) on the change of cerebral hemodynamics [regional cerebral blood flow(rCBF), pial arterial diameter(PAD) and mean arterial blood pressure(MABP)] in normal and cerebral ischemic rats. The change of rCBF and MABP were determinated by laser-doppler flowmetry(LDF), and the change of PAD was determinated by video-microscopy. The results in normal rats were as follows ; PMT significantly increased rCBF and PAD in a dose-dependent, and PMT increased MABP in a dose-dependent. This results were suggested that PMT significantly increased rCBF by dilating PAD. The results in cerebral ischemic rats were as follows ; Both rCBF and PAD were significantly and stably increased by PMT(10㎎/㎏, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. The present authors thought that PMT had an anti-ischemic effect through the improvement of cerebral hemodynamics.

Neuroprotective Effect of Sunghyangjungki-San on Focal Cerebral Ischemia Induced by MCAO in Rats (성향정기산이 흰쥐의 MCAO에 의한 국소뇌허혈에 미치는 영향)

  • Kim, Hyo-Sun;Kim, Youn-Sub
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.20 no.3
    • /
    • pp.596-602
    • /
    • 2006
  • This study evaluated neuroprotective effect of Sunghyangjungki-San (SHS) on the focal cerebral ischemia. The rats were induced infarct in cerebral cortex and caudoputamen by using temporal occlussion of the middle cerebral artery (MCAO), then water extract of SHS was treated for MCAO rats. Neuroprotective effect was evaluated by neurological score, infarct sizes and total volume, positive neurons against Bax, Caspase-3, HSP-72, and $HIF-1{\alpha}$ in infarct area with immunohistochemistry. The results obtained were as follows: Treatment of SHS improved neurological score of MCAO rats, but there was not a statistical significance. Treatment of SHS reduced significantly infarct sizes in the brain sections of MCAO rats. Treatment of SHS reduced significantly total volume of infarct of MCAO rats. Treatment of SHS reduced significantly Bax positive neurons in penumbra of cerebral cortex of MCAO rats. Treatment of SHS reduced significantly Caspase-3 positive neurons in caudoputamen and penumbra of cerebral cortex of MCAO rats. Treatment of SHS reduced significantly HSP-72 positive neurons in penumbra of cerebral cortex of MCAO rats. Treatment of SHS reduced significantly $IF-1{\alpha}$ positive neurons in penumbra of cerebral cortex of MCAO rats.

A preliminary study for the cerbral infarcted brain atrophy and osteoprosis via female reproductive physiology (Osteoporosis formation and alteration of female sex hormone after Cerebral Infarction) (여성의 뇌졸중후 골다공증에 대한 조경론적(調經論的) 기초연구)

  • Lee, Jong-Soo;Yoon, Sang-Hyub
    • The Journal of Korea CHUNA Manual Medicine
    • /
    • v.1 no.1
    • /
    • pp.125-137
    • /
    • 2000
  • the aim of this study was to investigate whether osteoporosis can be advanced after cerebral infarction Of not and role of female sex hormone. all animals were classified 4 groups; group of ovariectomy (OVXgroup) group of cerebral infarction( INF group), group of combination ovariectomy and cerebral infarction(OVX + INF group), naturally intact group for control data (NOR group ). cerebral infarction was made by Chen,s method with some modification and ovariectomy was performed by Wayforth,s method. experimental data was collected at 15 days, 1 month, 3 months and 6months after starting observation. serum 17 ${{\beta}-estradiol\;(E_2)}$ was determined by radioimmunoassay, for comparision of osteoporosis formation, bone density, serum osteocalcin, Serum total calcium and phosphorus, Serum AST Concentration, Serum ALT Concentration, Creatinine Concentration were also calculated. we have found that cerebral ischemia decreases not only the serum concentration of 17 ${{\beta}-estradiol\;(E_2)}$ and inhibits but also the physiologically compensatory function of the ovariectomized rats and that the decreased estrogen concentration followed by cerebral infarction have not produced osteoporosis, regretfully.

  • PDF

Effect of Cheonmabanhwa-tang on the Cerebral Hemodynamics in Rats (천마반하탕이 뇌혈류역학에 미치는 영향)

  • Yang Gi Ho;Jeong Hyun Woo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.18 no.1
    • /
    • pp.194-199
    • /
    • 2004
  • Cheonmabanhwa-tang(CBT) has been used in the Oriental Medicine for many centuries as a therapeutic agent for dizziness due to Poong-Dam. This study was designed to investigate whether CBT has a cytotoxicity in vitro, and affects the cerebral hemodynamics [regional cerebral blood flow(rCBF), pial arterial diameter(PAD), and mean arterial blood pressure(MABP)) in normal and cerebral ischemic rats. The changes of rCBF were determinated by laser-doppler f1owmeter(LDF), and the change of PAD was determinated by video-microscopy. The results in normal rats were as follows: CBT had no cytotoxicity in neuronal cells. CBT significantly increased rCBF. MABP and PAD in a dose-dependent manner, respectively. Both rCBF and PAD were significantly and stably increased by CBT(10 mg/kg, i.p.) during the period of cerebral reperfusion. which contrasted with the findings of rapid and marked increase in control group. In conclusion, it is suggested that CBT causes a diverse effect on cerebral hemodynamics thereby has an anti-ischemic action.

Effects of Nelumbinis Rhizomatis Nodus Extract on Cerebral Hemodynamics in Rats (연근 추출물이 뇌혈류역학에 미치는 효과)

  • Lee Keum-Soo;Jeong Hyun-Woo
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.19 no.6
    • /
    • pp.1546-1551
    • /
    • 2005
  • This Study was designed to investigate the effects of Nelumbinis Rhizomatis Nodus (NRN) on the change of cerebral hemodynamics [regional cerebral blood flow (rCBF), pial arterial diameter (PAD) and mean arterial blood pressure (MABP)] in normal and cerebral ischemic rats. And, this study was designed to investigate the inhibition of lactate dehydrogenase activity in neuronal cells The results were as follows NRN significantly increased rCBF and PAD in a dose-dependent manner, and NRN increased MABP in a dose-dependent manner. This results suggested that NRN significantly increased rCBF by dilating PAD. Both rCBF and PAD were significantly and stably increased by NRN (10 mg/kg, i.p.) during the period of cerebral reperfusion, which contrasted with the findings of rapid and marked increase in control group. NRN significantly inhibited lactate dehydrogenase activity in neuronal cells. This results suggested that NRN prevented the neuronal death. It is suggested that NRN had an anti-ischemic effect through the improvement of cerebral hemodynamics and inhibitive effect on the brain damage.

Experimental Study of Fraction of Citri Reticulatae Viride Pericarpium extract on the Brain Damage in Cerebral Ischemia (청파활성분획이 허혈성 뇌손상에 미치는 실험적 연구)

  • Rho Young Ho;Jeong Hyun Woo;Lee Won Suk
    • Journal of Physiology & Pathology in Korean Medicine
    • /
    • v.16 no.5
    • /
    • pp.893-898
    • /
    • 2002
  • Citri Reticulatae Viride Pericarpium extract(CRVP) have been used in oriental medicine for many centuries as a therapeutic agent for smoothing the liver and regulating the circulation of qi, and promoting digestion and removing stagnated food. The effects of CRVP on the inhibition of brain damage in cerebral ischemia is not known. Therefore, this Study was designed to investigate the cerebral protective effects of CRVP on the transient cerebral ischemia using modern techniques, and further to provide the possibility of scientification of oriental medicine. The size of cerebral infarct size was measured by morphometry, and brain edema was measured by morphometry and brain water content determination. The results were a$ follows ; 1. Water fraction of CRVP was reduced infect area of rats brain slices which were subjected to a transient cerebral ischemia in a dose-dependent manner. 2. Methylene chloride fraction and hexane fraction of CRVP was significantly reduced infarct area of rats brain slices which were subjected to a transient cerebral ischemia in a dose-dependent manner. 3. Methylene chloride fraction and hexane fraction of CRVP was significantly reduced infarct volume of rats brain which was subjected to a transient cerebral ischemia in a dose-dependent manner. 4. Methylene Chloride fraction and hexane fraction of CRVP was significantly decreased brain edema induced by a transient cerebral ischemia in a dose-dependent manner. 5. Methylene chloride fraction and hexane fraction of CRVP was significantly decreased brain water content of rats which were subjected to a transient cerebral ischemia. It is suggested that CRVP has an anti-ischemic effect through the inhibition of brain damage in a transient cerebral ischemia, and that in future further development of main effective constituent in CRVP can provide a novel therapeutic strategy for cerebral ischemia.