The kappa opioid receptor modulates GABA neuron excitability and synaptic transmission in midbrain projections from the insular cortex

As an integrative hub, the insular cortex (IC) translates external cues into interoceptive states that generate complex physiological, affective, and behavioral responses. However, the precise circuit and signaling mechanisms in the IC that modulate these processes are unknown. Here, we describe a midbrain-projecting microcircuit in the medial aspect of the agranular IC that signals through the Gαi/o-coupled kappa opioid receptor (KOR) and its endogenous ligand dynorphin (Dyn). Within this microcircuit, Dyn is robustly expressed in layer 2/3, while KOR is localized to deep layer 5, which sends a long-range projection to the substantia nigra (SN). Using ex vivo electrophysiology, we evaluated the functional impact of KOR signaling in layer 5 of the IC. We found that bath application of dynorphin decreased GABA release and increased glutamate release on IC-SN neurons, but did not alter their excitability. Conversely, dynorphin decreased the excitability of GABA neurons without altering synaptic transmission. Pretreatment with the KOR antagonist nor-BNI blocked the effects of dynorphin in IC-SN neurons and GABA neurons, indicating that the changes in synaptic transmission and excitability were selectively mediated through KOR. Selective inhibition of IC GABA neurons using a KOR-derived DREADD recapitulated these effects. This work provides insight into IC microcircuitry and indicates that Dyn/KOR signaling may act to directly reduce activity of layer 5 GABA neurons. In turn, KOR-driven inhibition of GABA promotes disinhibition of IC-SN neurons, which can modulate downstream circuits. Our findings present a potential mechanism whereby chronic upregulation of IC Dyn/KOR signaling can lead to altered subcortical function and downstream activity

Principals Application of Students’ Satisfaction and Leadership Principles of Total Quality Management for Secondary School Improvement in Anambra State

The main purpose of the study was to determine the principals’ application of students’ satisfaction and leadership principles of total quality management for secondary school improvement in Anambra State. Two research questions guided the study and two hypotheses were tested at 0.05 level of significance. The descriptive research design was adopted for the study. The study was carried out in Anambra State. The population of the study comprised 6664 principals and teachers (258 principals and 6406 teachers) from the 258 public secondary schools in the six education zones of the State. The sample of this study was 1999 respondents made up of 77 principals and 1922 teachers in secondary schools in Anambra State. A structured questionnaire was used to collect data. The instrument was validated by three experts in the Faculty of Education, Nnamdi Azikiwe University, Awka. The questionnaire reliability was ascertained through a pilot test. The data collected were analyzed with Cronbach Alpha and coefficient values of 0.75 and 0.77 for the two clusters with an overall reliability co-efficient value of 0.76 for the instrument. The data collected from the respondents were analyzed using descriptive statistics such as arithmetic mean and standard deviation and inferential statistics specifically the t-test. Findings revealed that principals applied students’ satisfaction and leadership principles to a moderate extent.</jats:p

Principals’ Environmental Supportive Administrative Services for Effective Classroom Management in Public and Private Secondary Schools in Anambra State

The purpose of this study is to analyse the environmental supportive administrative services provided by principals for effective classroom management in public and private secondary schools in Anambra State. One research question and one null hypothesis guided the study. It was a descriptive study conducted in Anambra state covering the six education zones in the state. A total of 15,990 respondents constituted the population for the study. A sample of 852 teachers was used. The instrument for data collection is a structured questionnaire developed by the researchers. The questionnaire was duly validated by experts who are lecturers. The reliability of the instrument was also established. Cronbach alpha statistic was used to determine reliability which gave the reliability coefficient of 0.81. The instrument was administered on the respondents directly by the researchers who assisted by six research assistants. Out of 852 copies of the questionnaire distributed, 850 copies were correctly filled, retrieved and subjected to statistical analysis. The data were analyzed using mean ratings to answer the research question and t- test to test the hypothesis at 0.05 level of significance. Findings indicated that, in public secondary schools, adequate workshops are not provided as part of environmental supportive administrative services for effective classroom management. Accordingly, it was among others recommended that government should organize workshops for secondary schools on environmental supportive administrative services.</jats:p

Principals’ Climate Change Supportive Administrative Services for Effective Classroom Management in Public and Private Secondary Schools in Anambra State

The purpose of this study is to analyse the climate change supportive administrative services provided by principals for effective classroom management in public and private secondary schools in Anambra State. The area of this study is Anambra state and the descriptive survey research design was used. There are six education zones namely Aguata, Awka, Nnewi, Ogidi, Onitsha, and Otuocha education zones. The population for this study comprised 15,990 respondents made up of 6,293 teachers in the 256 public secondary schools and 9,697 teachers in the 481 registered private secondary schools in Anambra state. The sample size for this study is 852 teachers. The instrument for data collection is a structured questionnaire developed by the researchers. The questionnaire was subjected to face validation using three experts who are lecturers. The reliability of the instrument was established using 100 teachers (50 in private secondary schools and 50 in public secondary schools) in 20 secondary schools in Enugu state. Cronbach alpha method was used to determine reliability of the items because the instrument is homogeneously structured. The reliability coefficient of the instrument was 0.74. The instrument was administered on the respondents directly by the researchers with the help of eight research assistants who are teachers in the various schools sampled. All the 852 copies of the questionnaire were correctly filled and retrieved. They were collated and subjected to statistical analysis. Data collected were analyzed using mean ratings to answer the research questions and t- test to test the hypotheses at 0.05 level of significance.</jats:p