• Title/Summary/Keyword: Neurobiology

Search Result 233, Processing Time 0.037 seconds

The Influence of Glutaraldehyde Concentration on Electron Microscopic Multiple Immunostaining

  • Bae, Jae Seok;Yeo, Eun Jin;Bae, Yong Chul
    • International Journal of Oral Biology
    • /
    • v.40 no.4
    • /
    • pp.183-187
    • /
    • 2015
  • The present study was aimed to evaluate the influence of glutaraldehyde (GA) concentration on multiple electron microscopic (EM) immunostaining using pre-embedding peroxidase and post-embedding immunogold method. Influence of various concentrations of GA included in the fixative on immuoreactivity was assessed in the multiple immunostaining using antisera against anti-transient receptor potential vanilloid 1 (TRPV1) for peroxidase staining and anti-GABA for immunogold labeling in the rat trigeminal caudal nucleus. Anti-TRPV1 antiserum had specificity in pre-embedding peroxidase staining when tissues were fixed with fixative containing paraformaldehyde (PFA) alone. Immunoreactivity for TRPV1 was specific in tissues fixed with fixative containing 0.5% GA at both perfusion and postfixation steps, though the immunoreactivity was weaker than in tissues fixed with fixative containing PFA alone. Tissues fixed with fixative containing 0.5% GA at the perfusion and postfixation steps showed specific immunogold staining for GABA. The results of the present study indicate that GA concentration is critical for immunoreactivity to antigens such as TRPV1 and GABA. This study also suggests that the appropriate GA concentration is 0.5% for multiple immunostaining with peroxidase labeling for TRPV1 and immunogold labeling for GABA.

Physiological and Pharmacological Characterization of Glutamate and GABA Receptors in the Retina

  • Yang, Xiong-Li;Shen, Ying;Han, Ming-Hu;Lu, Tao
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.3 no.5
    • /
    • pp.461-469
    • /
    • 1999
  • Glutamate and ${\gamma}-aminobutyric$ acid (GABA) are major excitatory and inhibitory neurotransmitters in the vertebrate retina, respectively. Using the whole-cell patch clamp technique and a rapid solution changer, glutamate and GABA receptors have been extensively investigated in carp retina. Glutamate receptors on both horizontal and amacrine cells may be an AMPA preferring subtype, which predominantly consists of flop splice variants. $GABA_A$ and $GABA_C$ receptors coexist in bipolar cells and they both show significant desensitization. Kinetics analysis demonstrated that activation, deactivation and desensitization of the $GABA_C$ receptor-mediated response of these cells are overall slower than those of the $GABA_A$ response. Endogenous modulator $Zn^{2+}$ in the retina was found to differentially modulate the kinetic characteristics of the $GABA_C$ and $GABA_A$ responses.

  • PDF

Quantitative Analysis of Neurotransmitters in the Endings Presynaptic to Vibrissa Afferent Terminals in the Cat Trigeminal Caudal Nucleus (고양이 삼차신경꼬리핵에서 저역치기계자극수용기 유래 들신경종말의 연접이전종말이 함유하는 신경전달물질에 대한 정량적 분석)

  • Kim, Yun-Sook;Mun, Cheol-Ju;Cho, Jin-Hyun;Bae, Jin-Young;Na, Yeon-Kyung;Bok, Hye-Jeong;Bae, Yong-Chul;Paik, Sang-Kyoo
    • Applied Microscopy
    • /
    • v.42 no.1
    • /
    • pp.9-16
    • /
    • 2012
  • The goal of this study was to identify neurotransmitters in endings (p-endings) presynaptic to low-threshold mechanoreceptive vibrissa afferents in the laminae III/IV of cat trigeminal caudal nucleus (Vc). Rapidly-adapting vibrissa afferents were intra-axonally labeled after electrophysiological identification, and postembedding immunogold staining with antisera against ${\gamma}$-aminobutyric acid (GABA) and glycine was performed, followed by quantitative ultrastructural analysis of p-endings presynaptic to the labeled vibrissa afferent terminals. Sixteen p-endings, which are presynaptic to the HRP-labeled vibrissa afferent terminals, were analyzed in this study: Eight p-endings (50%, 8/16) were immunopositive to GABA but immunonegative to glycine (GABA+ p-ending), and remaining 8 p-endings (50%, 8/16) exhibited immunoreactivity to both GABA and glycine. Bouton volume of the p-endings was not significantly different between the two groups. However, the p-endings differed from each other in relative content of GABA and glycine. These findings suggest that low-threshold mechanoreceptive information conveyed through vibrissa afferent at Vc is presynaptically modulated by GABA and/or glycine, and that degree of presynaptic modulation may differ among each vibrissa afferent terminal.

Cardiac physiologic regulation of sub-type specific adrenergic receptors in transgenic mice overexpressing β1- and β2-adrenergic receptors.

  • Kim, Ka Eul;Tae, Hyun-Jin;Natalia, Petrashevskaya;Lee, Jae-Chul;Ahn, Ji Hyeon;Park, Joon Ha;Kim, In Hye;Ohk, Taek Geun;Park, Chan Woo;Cho, Jun Hwi;Won, Moo-Ho
    • Clinical and Experimental Emergency Medicine
    • /
    • v.3 no.3
    • /
    • pp.175-180
    • /
    • 2016
  • Objective Combination of ${\beta}_1-adrenergic$ receptor (AR) blockade and ${\beta}_2-AR$ activation might be a potential novel therapy for treating heart failure. However, use of ${\beta}-AR$ agonists and/or antagonists in the clinical setting is controversial because of the lack of information on cardiac inotropic or chronotropic regulation by AR signaling. Methods In this study, we performed hemodynamic evaluation by examining force frequency response (FFR), Frank-Starling relationship, and response to a non-selective ${\beta}-AR$ agonist (isoproterenol) in hearts isolated from 6-month-old transgenic (TG) mice overexpressing ${\beta}_1-$ and ${\beta}_2-ARs$ (${\beta}_1-$ and ${\beta}_2-AR$ TG mice, respectively). Results Cardiac physiologic consequences of ${\beta}_1-$ and ${\beta}_2-AR$ overexpression resulted in similar maximal response to isoproterenol and faster temporary decline of positive inotropic response in ${\beta}_2-AR$ TG mice. ${\beta}_1-AR$ TG mice showed a pronounced negative limb of FFR, whereas ${\beta}_2-AR$ TG mice showed high stimulation frequencies with low contractile depression during FFR. In contrast, Frank-Starling relationship was equally enhanced in both ${\beta}_1-$ and ${\beta}_2-AR$ TG mice. Conclusion Hemodynamic evaluation performed in the present showed a difference in ${\beta}_1-$ and ${\beta}_2-AR$ signaling, which may be due to the difference in the desensitization of ${\beta}_1-$ and ${\beta}_2-ARs$.