• International Journal of Oral Biology
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• 제41권1호
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• pp.25-32
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• 2016

The tongue has 4 kinds of papillae, which are filiform, fungiform (FU), foliate (FO) and circumvallate papilla (CV). Tongue papillae except filiform papilla include taste buds. The papillae differ in taste sensitivities, likely due to differential expression of taste receptors. In this study, we evaluated differences in the expression levels of taste receptors in FU, FO and CV. Male DBA2 mice, 42-60 days old, were used in the study. Messenger RNAs were extracted from the murine epithelial tissues including FU, FO and CV. Cloned DNAs were synthesized by reverse transcription. Quantitative PCRs (qPCRs) were performed to determine mRNA expression levels of taste receptors. Results of qPCR revealed that the relative expression levels and patterns were different among FU, FO and CV. All three type 1 taste receptors were expressed FU, FO and CV at varying relative expression levels. All 35 kinds of type 2 taste receptors showed higher expression in FO and CV than in FU. Tas2r108 and Tas2r137 showed the two highest expression levels in all tested papillae. The differential expression levels and patterns of taste receptors among the three papillae could contribute to the different physiological sensitivities by tongue areas. Additional studies such as in situ hybridization or taste receptor cell activity recording is necessary to elucidate the functional relationship between expression levels of taste receptors and taste sensitivity.

• 약학회지
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• 제44권1호
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• pp.52-59
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• 2000

An exceptionally conserved sequence that is shared among most G protein-coupled neurotransmitter receptors is an aspartate-arginine-tyrosine triplet that is located at the second cytoplasmic domain. Using the ml subtype of muscarinic acetylcholine receptors as an example, a point mutation of the arginine residue at position 123 into asparagine was induced. This mutation resulted in a complete blockade of the carbachol-induced increases of PI hydrolysis and intracellular $Ca^2$$^{+}$ level, in spite of the expression of the wild-type and mutant receptors at similar concentrations in Chinese hamster ovary cells. In marked contrast, the muscarinic agonist carbachol induced concentration-dependent enhancement of the activity of NO synthase at mutant ml receptors although the enhancement was significantly smaller than at wild-type ml receptors. These data suggest that this highly conserved arginine residue plays an important role in coupling of muscarinic receptors to the second messenger systems and the presence of alternate mechanisms of activation of neuronal NO synthase which might be operative in the absence of large changes in the concentration of cellular $Ca^{2+}$.2+/.

• Archives of Pharmacal Research
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• 제22권1호
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• pp.35-43
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• 1999

Overstimulation of both kainate (KA) and N-methyl-D-aspartate (NMDA) receptors has been reported to induce excitatoxicity which can be characterized by neuronal damage and formation of reactive oxygen free radicals. Neuroprotective effect of melatonin against KA-induced excitotoxicity have been documented in vitro and in vivo. It is, however, not clear whether melationin is also neuroportective against excitotoxicity mediated by NMDA receptors. In the present work, we tested the in vivo protective effects of striatally infused melatonin against the oxidative stress and neuronal damage induced by the injection of KA and NMDA receptors into the rat striatum. Melatonin implants consisting of 22-gauge stainless-steel cannule with melatonin fused inside the tip were placed bilaterally in the rat brain one week prior to intrastriatal injection of glutamate receptor subtype agonists. Melatonin showed protective effects against the elevation of lipid peroxidation induced by either KA or NMDA and recovered Cu, Zn-superoxide dismutase activities reduced by both KA and NMDA into the control level. Melatonin also clearly blocked both KA- and NMDA-receptor mediated neuronal damage assessed by the determination of choline acetyltransferase activity in striatal monogenages and by microscopic observation of rat brain section stained with cresyl violet. The protective effects of melatonin are comparable to those of DNQX and MK801 which are the KA- and NMDA-receptor antagonist, respectively. It is suggested that melatonin could protect against striatal oxidative damages mediated by glutamate receptors, both non-NMDA and NMDA receptors.

• Biomolecules & Therapeutics
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• 제31권4호
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• pp.359-369
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• 2023

Dependence receptors are a group of receptor proteins with shared characteristics of transducing two different signals within cells. They can transduce a positive signal of survival and differentiation in the presence of ligands. On the other hand, dependence receptors can transduce an apoptosis signal in the absence of ligands. The function of these receptors depends on the availability of their ligands. Several receptor tyrosine kinases (RTKs) have been reported as dependence receptors. When cells undergo apoptosis by dependence receptors, the intracellular domain of some RTKs is cleaved by the caspases. Among the RTKs that belong to dependence receptors, we focused on eight RTKs (RET, HER2, MET, ALK, TrkC, EphA4, EphB3, and c-KIT) that are cleaved by caspases. In this review, we describe the features of the receptors, their cleavage sites, and the fate of the cleaved products, as well as recent implications on them being used as potential therapeutics for cancer treatment.

• 한국전문물리치료학회지
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• 제3권2호
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• pp.95-105
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• 1996

지금까지의 내용을 요약하면 먼저, 인체의 각 관절 주위에는 관절의 움직임과 위치를 파악하는 감지기 역할을 하는 기계적 감수기가 있다. 이러한 감수기는 크게 네가지로 구분되어지는데 대개 I형 감수기, II형 감수기 등의 용어를 사용한다. 각각의 감수기의 특성(표 2.)을 알아보면, 루피니(Ruffini)감각기와 유사한 모양을 하고 있는 I형 관절감수기는 주로 운동의 속도(speed)와 방향(direction)을 감지(detection) 하며, 파시니안(Pacinian)감각기와 유사한 형태를 하고 있는 II형 관절감수기는 매우 작은 움직임에 대한 감지를 하는데, 예를 들어 속도가 가속(acceleration)되는 것과 같은 움직임 등을 알아낸다. 이외에 골지건과 비슷한 모습을 하고 있는 III형 관절감수기는 운동의 자세(position)와 방향에 대한 정보를 전달하게 된다 (Carpanter, 1990). 관절의 자세 유지 혹은 안정성 즉, 정적(static) 운동에 주로 관여하는 I형 관절감수기와, 역동적(dynamic)인 운동에 감지를 주로 하는 II형 관절감수기는 진동(oscillation)자극에 잘 촉진된다. 이러한 자극은 동통이 심하게 발생된 관절에 나타나는 근육의 과긴장(hypertonicity)과 동통을 경감시킬 수 있다. III형 관절감수기는 억제 (inhibitory)감수기라 할 수 있는데, 골지건(golgi tendon organ)의 기능과 매우 관련이 깊다. 이 감수기는 관절의 가동범위를 기계적인 자극으로 증가시키기 위해 관절의 가동 끝범위에서 강한 신장(strong strectch)이나 thrust 기술로 감수기를 촉진할 수 있다. 이러한 자극은 결국 근육에 이완을 얻게 할 수 있다. 위에서 언급한 관절 주위의 조직에 분포한 특별한 기계적 감지를 환자들의 임상 증상에 따라 선택적으로 자극하는 치료를 적용할 수 있다면, 현재 물리치료사들이 적용하고 있는 관절 가동운동을 좀더 전문적인 수준으로 수행할 수 있을 것이다.

• Molecules and Cells
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• 제40권12호
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• pp.954-965
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• 2017

Mammalian genomes are well established, and highly conserved regions within odorant receptors that are unique from other G-protein coupled receptors have been identified. Numerous functional studies have focused on specific conserved amino acids motifs; however, not all conserved motifs have been sufficiently characterized. Here, we identified a highly conserved 18 amino acid sequence motif within transmembrane domain seven (CAS-TM7) which was identified by aligning odorant receptor sequences. Next, we investigated the expression pattern and distribution of this conserved amino acid motif among a broad range of odorant receptors. To examine the localization of odorant receptor proteins, we used a sequence-specific peptide antibody against CAS-TM7 which is specific to odorant receptors across species. The specificity of this peptide antibody in recognizing odorant receptors has been confirmed in a heterologous in vitro system and a rat-based in vivo system. The CAS-TM7 odorant receptors localized with distinct patterns at each region of the olfactory epithelium; septum, endoturbinate and ectoturbinate. To our great interests, we found that the CAS-TM7 odorant receptors are primarily localized to the dorsal region of the olfactory bulb, coinciding with olfactory epithelium-based patterns. Also, these odorant receptors were ectopically expressed in the various non-olfactory tissues in an evolutionary constrained manner between human and rats. This study has characterized the expression patterns of odorant receptors containing particular amino acid motif in transmembrane domain 7, and which led to an intriguing possibility that the conserved motif of odorant receptors can play critical roles in other physiological functions as well as olfaction.

• 대한정형도수물리치료학회지
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• 제2권1호
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• pp.9-19
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• 1996

지금까지의 내용을 요약하면 먼저, 인체의 각 관절 주위에는 관절의 움직임과 위치를 파악하는 감지기 역할을 하는 기계적 감수기가 있다. 이러한 감수기는 크게 네가지로 구분되어지는데 대개 I 형 감수기, II 형 감수기 등의 용어를 사용한다. 각각의 감수기의 특성(표 2.)을 알아보면, 루피니(Ruffini)감각기와 유사한 모양을 하고 있는 I 형 관절감수기는 주로 운동의 속도(speed)와 방향(direction)을 감지(detection)하며, 파시니안(Pacinian)감각기와 유사한 형태를 하고 있는 II 형 관절감수기는 매우 작은 움직임에 대한 감지를 하는데, 예를 들어 속도가 가속(acceleration)되는 것과 같은 움직임 등을 알아낸다. 이외에 골지건과 비슷한 모습을 하고 있는 II 형 관절감수기는 운동의 자세(position)와 방향에 대한 정보를 전달하게 된다. 관절의 자세 유지 혹은 안정성 즉, 정적(static) 운동에 주로 관여하는 I 형 관절감수기와, 역동적(dynamic)인 운동에 감지를 주로하는 II 형 관절감수기는 진동(oscillation)자극에 잘 촉진된다. 이러한 자극은 동통이 심하게 발생된 관절에 나타나는 근육의 과긴장(hypertonicity)과 동통을 경감시킬 수 있다. III 형 관절감수기는 억제(inhibitory)감수기라 할수 있는데, 골지건(Golgi tendon organ)의 기능과 매우 관련이 깊다. 이 감수기는 관절의 가동범위를 기계적인 자극으로 증가시키기 위해 관절의 가동 끝범위에서 강한 신장(strong stretch)이나 thrust 기술로 감수기를 촉진할 수 있다. 이러한 자극은 결국 근육에 이완을 얻게 할 수 있다. 위에서 언급한 관절 주위의 조직에 분포한 특별한 기계적 감지를 환자들의 임상 중상에 따라 선택적으로 자극하는 치료를 적용할 수 있다면, 현재 물리치료사들이 적용하고 있는 관절 가동운동을 좀 더 전문적인 수준으로 수행할 수 있을 것이다.

• International Journal of Oral Biology
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• 제33권1호
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• pp.13-23
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• 2008

Taste is a critically important sense for the survival of an organism. However, structure and distribution of taste receptors were only recently investigated. Although expression of the ion channels responsible for the sense of salty taste and acidity was observed in the non-taste cells, receptors for sweet and bitter taste were only identified in taste cells. Salivary glands are involved in the sensing of taste and plays important roles in the transduction of taste. The purpose of this study is to examine whether taste receptors are present in the salivary glands and to provide clues for the investigation of the taste-salivary glands interaction. Using microarray and RT-PCR analyses, the presence of taste receptor mRNAs in the rat von Ebner gland and submandibular gland was confirmed. Type I taste receptors were preferentially expressed in von Ebner gland, whereas type II taste receptors were expressed in both von Ebner gland and submandibular gland. The tastespecific signal tranducing proteins, $G_{\alpha}gustducin$ and phospholipase C ${\beta}2$, were also detected in both salivary glands by immunohistochemistry. Finally, the activation of the calcium signal in response to bitter taste in the acinar cells was also observed. Taken together, these results suggest that taste receptors are present in the von Ebner gland and submandibular gland and that type II taste receptors are functionally active in both salivary glands.

• Archives of Pharmacal Research
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• 제14권3호
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• pp.271-278
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• 1991

To investigate further whether the effects of the dihydropyridine (DHP) drugs on calcium channels are related to those of these drugs on muscarinic receptors, the binding characteristics of the DHP calcium channel agonist, Bay K 8644, on muscarinic receptors and calcium channels were compared to those of the DHP calcium channel antagonists, nicardipine and nimodipine in the dog cardiac sarcolemma. Bay K 8644, nicardipine and nimodipine inhibited the specific $[^3H]$QNB binding with $K_i$ values of 16.7\mu{M}$, 3.5\mu{M}$ and 15.5\mu{M}$ respectively. Saturation data of $[^3H]$QNB binding with $K_i$ VALUES OF 16.7\mu{M}$ 3.5\mu{M}$ and 15.5\mu{M}$ respectively. Saturation data of $[^3H]$QNB binding in the presence of these DHP drugs showed this inhibition to be competitive. Bay K 8644, like nicardipine and nimodipine, blocked the binding of $[^3H]$nitrendipine to the high affinity DHP binding sites, but atropine did not, indicating that the muscarinic receptors and the DHP binding sites m but atropine did not, indicating that the muscarinic receptors and the DHP bindings sites on calcium channels are distinct. The $K_i$ value of Bay K 8644 for the DHP binding sites was 4nM. Nicardipine and nimodipine $(K_i:0.1-0.2\;nM)$ were at least 20 times more potent than Bay K 8644 in inhibiting $[^3H]$ nitrendipine binding. Thus, the muscarinic receptors were about 4000 times less sensitive than thes high afinity DHP binding sites to Bay K 8644. These results suggest that the DHP calcium agonist Bay K 8644 binds directly to the muscarinic receptors but its interaction with the muscarinic receptors is not related to its binding to the DHP binding sites on calcium channels.

• Journal of Ginseng Research
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• 제21권3호
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• pp.147-152
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• 1997

Ginsenosides $Rh_1$ and $Rh_2$ Induced the differentiation of F9 teratocarcinoma stem cells. These agents are structurally similar to the steroid hormones, therefore, we speculated that the steroid receptor (s) or novel nuclear receptor (s) could be involved in the differentiation process induces by them. Based on this speculation, we tried to alone new nuclear receptors with reverse transcription-polymerase chain reaction (RT-PCR) method by isolating RNA from F9 teratocarcinoma cells induced by ginsenosides. By using RT-PCR with degenerated primers from highly conserved DNA binding domain of nuclear receptors, we identified several nuclear receptors. In northern blot analysis we found that these clones are transcriptionally regulated by ginsenoside Rhl or Rh2 treatment. Further characterizations of these clones are needed to identify the mechanism of gene expression, which has an important role in the differentiation of F9 cells induced by ginsenosides.